Vertebral stabilization assembly and method

ABSTRACT

A vertebral stabilization assembly for stabilizing vertebrae is provided. The vertebral stabilization assembly includes a first and a second pedicle screw, a first and second connecting screw, and a connecting member. The first and second pedicle screws each have a shaft provided with a threaded portion operable for threading engagement of the first and second pedicle screws with a first and second vertebra, respectively, each shaft also has an engaging portion. The first and second connecting screws each have a first end adapted to be received by the engaging portions of the first and second pedicle screws, respectively. The connecting member has a first end connected to the first connecting screw and a second end connected to the second connecting screw for stabilization of the first and second vertebra. A guide member for placement of the connecting screw and method for anteriorly stabilizing vertebrae is also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] Pursuant to 35 U.S.C. §119(e), this application claims thebenefit of U.S. Provisional Patent Application No. 60/327,118, entitledVertebral Stabilization Assembly and Method, filed Oct. 3, 2001, andU.S. Provisional Patent Application No. 60/350,259, entitled VertebralStabilization Assembly and Method Having a Modified Pedicle Screw, filedNov. 2, 2001, and U.S. Provisional Patent Application No. 60/331,857entitled Vertebral Stabilization Assembly and Method for AnteriorPlacement, filed Nov. 20, 2001, and U.S. Provisional Patent ApplicationNo. 60/353,691, entitled Vertebral Stabilization Assembly and MethodHaving Dual Pedicle Screws, filed Jan. 31, 2002, all naming Paul A.Vaughan as inventor, which are hereby incorporated by reference for allpurposes.

TECHNICAL FIELD OF THE INVENTION

[0002] The present invention relates generally to a spinal stabilizationand more specifically, but not by way of limitation, to a vertebralstabilization assembly and method for stabilizing vertebra.

BACKGROUND OF THE INVENTION

[0003] The human spine frequently requires surgery to repair deformitiesor injuries. Spinal problems may be caused by a trauma to the spinereceived during an accident, excessive strain or stress on the spinefrom physical activities, a sedentary lifestyle and poor posture thatmay place abnormal pressure on the spine, disease or a variety of otherreasons. Spinal fusion is a common surgery intended to alleviate paincaused by these spinal deformities or injuries.

[0004] The spinal fusion procedure generally includes removing the disk,packing bone graft between the vertebrae and placing a spinal implant,such as screws attached to a plate, rod or cage, to fuse elements of thespine together. Once the disk is removed and the bone graft is placedbetween the vertebrae, the bone graft will fuse to the vertebrae over aperiod of several months following the surgery.

[0005] The purpose of the plate is to stabilize the vertebrae until thebone graft has become fused to the vertebrae. The plate is positioned toextend between at least two vertebrae. The plate is attached to screwsanchored in each of the adjacent vertebrae, thus immobilizing thedesired portion of the spine. The plate is anchored to the screws eitheron the front, anterior, or back, posterior, sides of the vertebrae.

[0006] The present invention is not intended to be limited toapplications in a specific region of the spine, and may, in fact, beutilized equally well with the cervical, thoracic, lumbar and sacrumvertebrae of the spine. However, for purposes of explanation, thesurgical procedure will be discussed in greater detail with respect onlyto the lumbar vertebrae region of the spine. Procedurally, anterior, orentry from the stomach region of the patient, lumbar vertebra surgeryprovides the surgeon with optimum access to the entire intervertebraldisk. Posterior, or entry from the back of the patient, surgery is lesspreferred since access to the disk is restricted. Once the anteriorlumbar discectomy, or removal of the lumbar disk, is completed, the bonegraft is placed into the space between the vertebrae previously occupiedby the disk.

[0007] The patient is then positioned for posterior fusion, orplacement, of the plate. The stabilization is typically accomplished byplacing a screw in each of the lumbar vertebra such the screw extendsthrough a portion of the vertebra and into the body of the vertebra.Each screw extends posteriorly from the vertebra sufficient forattachment to the plate. The plate is then anchored to each of thescrews to retain the adjacent lumbar vertebrae positioned a distancefrom each other. The plate and screws thereby stabilize the lumbarvertebrae and provide time for the vertebrae and bone graft to fuse intoa solitary unit.

[0008] However, posterior fusion requires large posterior muscledissection to safely implant the pedicle screws and provide forplacement of the plate. Such major muscle damage presents a danger tothe patient during surgery from infection and the extensive muscledamage. Also, additional time is required to perform both extensiveanterior and posterior surgical portions. The added surgical timepresents another risk to the patient.

[0009] Attempts to eliminate the negative aspects of posterior fusioninclude anterior placement of the plate and screws. Although anteriorfusion avoids the problems associated with the larger posterior fusion,additional problems arise. In such systems, the anchoring screws arelaterally placed on the anterior of the vertebra. Lateral placementrequires a significantly more invasive procedure and much greaterexposure. Also, screws anchored laterally through the anterior of thevertebra do not provide the stability of those extending posteriorlythrough the pedicle and into the vertebral body. Furthermore,anteriorly-anchored screws do not promote quick and uniform fusion ofthe bone graft to the vertebra since they do not have the stability ofthe pedicle fixation.

[0010] Thus a need exists for a vertebral stabilization assembly thatobtains the benefits while overcoming the disadvantages of priorprocedures and systems.

SUMMARY OF THE INVENTION

[0011] The present invention provides a vertebral stabilization assemblyfor stabilizing vertebra. The vertebral stabilization assembly includesa first and a second pedicle screw, a first and a second connectingscrew and a connecting member. The first pedicle screw has a shaftprovided with a threaded portion operable for threading engagement ofthe first pedicle screw with a first vertebra, the shaft also has anengaging portion. The first connecting screw has a first end adapted tobe received by the engaging portion of the first pedicle screw.

[0012] The second pedicle screw has a shaft provided with a threadedportion operable for threading engagement of the pedicle screw with asecond vertebra. The shaft of the second pedicle screw has an engagingportion. The second connecting screw has a first end adapted to bereceived by the engaging portion of the second pedicle screw. Theconnecting member has a first end and the second end. The first end ofthe connecting member connected to the first connecting screwpositionable in the first vertebra. The second end of the connectingmember connected to the second connecting screw positionable in thesecond vertebra for stabilization of the first vertebra and the secondvertebra.

[0013] In one aspect, the connecting member may be a rod, bracket, plateor brace. In other aspects, the first and second connecting screws areeach provided with an opening in a second end thereof and wherein thefirst end of the rod is positionable in the opening in the second end ofthe first connecting screw and wherein the second end of the rod ispositionable in the opening in the second end of second connectingscrew.

[0014] In one aspect, the present invention further comprises a firstand second tensioning mechanism, the first tensioning mechanismtensioningly engaging the first end of the rod in the opening in thesecond end of the first connecting screw and the second tensioningmechanism tensioningly engaging the second end of the rod in the openingin the second end of the second connecting screw.

[0015] In other aspects, the first and second connecting screws areprovided with coupling portions operable to couple the first and secondconnecting screws with the connecting member. In other aspects, thecoupling portions of the first and second connecting screws are furtherdefined as a threaded end of the first and second connecting screws.

[0016] In other aspects, the threaded end of the first and secondconnecting screws are connectable to the connecting member by bolts.While in other aspects, the connecting member connected to the first andsecond connecting screw is sized to retain the first vertebra disposed adistance from the second vertebra. The connecting member may be sized toretain the first vertebra disposed so as to prevent contact with thesecond vertebra.

[0017] In other aspects, the first and second pedicle screws areoperable to engage a first and second lumbar vertebra, respectively.

[0018] In yet another aspect the vertebral stabilization assemblyfurther includes a bore screw having a shaft sized similar in diameterto the shaft of the first and second pedicle screw. In one aspect, thediameter of the shaft of the bore screw is substantially similar to thediameter of the shaft of the pedicle screw, while in other aspects thediameter of the shaft of the bore screw is smaller, and in otherslarger, than the diameter of the shaft of the pedicle screw The borescrew is operative to bore an opening in the vertebra, from theposterior side of the vertebra.

[0019] The bore screw is useful to create a bore opening in the vertebrathat is at a desirable angle in the vertebra. The bore screw may then belocated from the anterior side and removed anteriorly according to oneaspect or removed posteriorly according to another aspect of the presentinvention. Where the bore screw is removed anteriorly, the bore screw isprovided with an engaging portion on a distal end of the bore screw forconnection of the bore screw by a tool for removal from the vertebralanterior.

[0020] One advantage of utilizing the bore screw is that the angle ofplacement of the bore screw is known so that the proper pedicle screwmay be selected based on the angle of penetration of the bore openingcreated in the vertebra by the bore screw, such as a pedicle screwhaving a engaging portion with the proper angle of connection forattachment of the connecting screw and a pedicle screw of appropriatelength.

[0021] In another aspect, the vertebral stabilization assembly of thepresent invention further includes an indicator positionable posteriorlyadjacent the bore opening created by bore screw. The indicatorindicating the location of the bore opening from the anterior side ofthe vertebra. In one aspect, the indicator is an LED (light emittingdiode) disposed on a rigid shaft extendable down the bore opening nearthe anterior side of the vertebra. In other aspects, the shaft may besubstantially flexible for easy removal. In other aspects, the indicatoris an LED or higher intensity light, such as a laser light, and isdisposed posteriorly near the bore opening such that the light projectsdown the opening and is perceptible from the vertebral anterior.

[0022] In another aspect the present invention provides a pedicle screwfor securing a connecting screw of a vertebral stabilization assembly.The pedicle screw includes a shaft, an engaging portion and couplingportion. The shaft has a threaded portion operable for threadingengagement of the pedicle screw with a vertebra. The engaging portion isprovided on the shaft and operable to receive a connecting screw of thevertebral stabilization assembly. The coupling portion is provided onthe shaft and adapted to connect a guide member of the vertebralstabilization assembly. In one aspect of the pedicle screw of thepresent invention the shaft is cannulated. The cannulated portion of theshaft further defined as a passageway extending through the shaft from afirst end of the shaft to a second end of the shaft.

[0023] In one aspect, the shaft is further defined as having a first endand a second end such that the threaded portion is adjacent the firstend and the second end is operable to receive rotational engagement forrotating the pedicle screw. In yet another aspect, the engaging portionis further defined as an opening on the shaft operable to receive theconnecting screw of the vertebral stabilization assembly.

[0024] In other aspects, the opening is further defined as extendingthrough the shaft from a shaft first side to a shaft second side. Inanother aspect, the opening is coupleable with the connecting screw toprovide stabilizing engagement of the connecting screw. While yet otheraspects provide the opening is coupleable with the connecting screw toprovide rigid engagement with the connecting screw.

[0025] In one aspect, the engaging portion is coupleable with theconnecting screw to provide locking engagement with the connectingscrew. In other aspects, the engaging portion is coupleable with theconnecting screw to provide threaded engagement with the connectingscrew. In yet other aspects, the coupling portion of the shaft isassociated with the opening in the shaft such when the guide member iscoupled to the coupling portion an alignment member of the guide memberis aligned with the engaging portion in the shaft.

[0026] In one aspect, the coupling portion is further defined as anopening operable for threading engagement. In another aspect, the shaftis further defined as a substantially rigid shaft constructed from amaterial selected from the group consisting of steel, aluminum, metallicmaterials and polymeric materials. While in other aspects, the shaft issubstantially cannulated such that a passageway extends through theshaft from a first end of the shaft to a second end of the shaft. In oneaspect, the pedicle screw is operable to engage a lumbar vertebra. Inanother aspect, the pedicle screw is further operable to engage athoracic vertebra.

[0027] In one aspect, the engaging portion on the shaft of the pediclescrew includes rotational portion for rotating the engaging portion forreceiving the connecting screw at various angles relative to the shaftof the pedicle screw. In some aspects, the rotational portion includes ahinging member or a ratcheting member operative for rotation of theengaging portion. In other aspects, the engaging portion is disposed inan engaging opening in the shaft of the pedicle such that the engagingportion is rotatable within the engaging opening and, in some aspects,becomes fixed or locked when the connecting screw is received by theengaging portion.

[0028] In one aspect, the shaft of the pedicle screw is provided with atleast one non-continuous thread extending circumferentially about theshaft such that at least one gap is disposed between a first portion ofthe non-continuous thread and a second portion of the non-continuousthread. The advantage of the disposition of the non-continuous thread isthat when the nerve is aggravated by the placement of the pedicle screw,the pedicle screw may be rotated into a position such that the gap isadjacent the aggravated nerve instead of the thread to alleviate theaggravation which may be caused by the threaded portion of the shaft ofthe pedicle screw.

[0029] In another aspect, the shaft of the pedicle screw is providedwith a first threaded portion and a reinforced portion. The reinforcedportion of the shaft has a diameter that is greater than a diameter ofthe first threaded portion of the shaft. In one aspect, the reinforcedportion of the shaft is substantially adjacent the engaging portion ofthe shaft for reinforcing the connection of the connecting screw to thepedicle screw via the engaging portion.

[0030] In another aspect the reinforced portion of the shaft is adjacentthe first threaded portion and adjacent a second threaded portion, thediameter of the reinforced portion is greater than the diameter of thefirst threaded portion and about equal to a diameter measured from anoutermost edge of a plurality of threads provided on the first threadedportion of the shaft. The diameter of the reinforced portion of theshaft is less than a diameter measured from an outermost edge of aplurality of threads provided on the second threaded portion of theshaft. The reinforced portion of the shaft is one advantage of thepresent aspect since the stability of the vertebral stabilizationassembly is significantly enhanced by the additional structural supportprovided by the reinforced portion for connection of the connectingscrew to the engaging portion of the pedicle screw adjacent thereinforced portion.

[0031] In yet another aspect, the shaft of the pedicle screw has atleast a first groove extending a distance along the length of the shaft.In one aspect, a distal end of the shaft of the pedicle screw issubstantially conical, while in other aspects, the distal end of theshaft is a substantially flat surface. In one aspect, where the distalend of the shaft is a substantially flat surface, the pedicle screw isprovided with a cap which may have a conically shaped first end and asecond end configured for mating connection near the distal end of thepedicle screw. In this aspect, the mating connection may be achieved byproviding a recess in at least the first groove on the shaft and a notchon an inner surface of the cap such that the notch on the inner surfaceof the cap is tensioningly received by the recess in at least the firstgroove of the shaft.

[0032] In one aspect, the distal end of the pedicle screw isrectangularly configured for mating with a guide member for properalignment of the engaging portion of the pedicle screw for connection ofthe connecting screw. In one aspect, only a portion of the shaft isprovided with threads. In this aspect, the threads may be providedexcept on a portion of the shaft substantially adjacent the engagingportion. In other aspects, only a portion of the shaft above theengaging portion is provided with threads, while in other aspects only aportion of the shaft below the engaging portion is provided withthreads.

[0033] In yet another aspect, the pedicle screw has a first end providedwith a head operative for rotational engagement of the pedicle screwwith the vertebra. A coupling portion is disposed adjacent the first endthe pedicle screw and is further operative to engage a guide member ofthe vertebral stabilization assembly. In this aspect, the pedicle screwis provided for anterior placement such that a distal end of the pediclescrew which initially penetrates the vertebra from an anterior side ofthe vertebra engages and stabilizes from within the body portion of thevertebra near the pedicle of the vertebra. After placement of thepedicle screw, the head of the pedicle screw is disposed adjacent theanterior side of the vertebra for receiving a guide member.

[0034] One advantage of the pedicle screw for anterior placement andstabilization is that, when utilizing this aspect of the pedicle screw,placement of the vertebral stabilization assembly may be accomplishedentirely from the patient's anterior eliminating the need to rotate thepatient and further reducing the time needed for the surgical procedure.Utilizing the present aspect of the pedicle screw for anterior placementand stabilization provides numerous advantages even where portions ofthe medical procedure are accomplished from the patient's posterior. Forexample, in some aspects, it may be useful and necessary to rotate thepatient and perform significant or peripheral procedures from thepatient's posterior during certain portions of the vertebralstabilization procedure.

[0035] In yet other embodiments, the present invention provides a toolconfigured to connect to the distal end of the pedicle screw. In oneaspect, the tool is provided with a first end having a handle adapted tobe grasped by the hand of an individual and a second end provided with aconnector to connect to the distal end of the pedicle screw to retainand stabilize the pedicle screw for placement and removal of theconnecting screw. In one aspect the distal end of the pedicle screw isprovided with an opening and the second end of the tool is provided witha connector configured to be received into the opening in the distal endof the pedicle screw for securing the pedicle screw.

[0036] In yet another aspect, the connecting screw is provide with atleast a first groove on a shaft portion of the connecting screw forconnection by a tool for retaining the connecting screw for placementand removal of the connecting screw. In one aspect, the connecting screwhas an opening on one end of the connecting screw, and the tool isprovided with a connector adapted to be received by the opening andconfigured to connect to the tool.

[0037] In yet another aspect, the present invention provides a guidemember for placement of a screw of a vertebral stabilization assembly.The guide member including a coupling portion, and offset member, and analignment member. The coupling portion is operable to couple with acoupling portion of a pedicle screw of the vertebral stabilizationassembly. The offset member is connected to the coupling portion of theguide member. The offset member extending from the coupling portionrelative to the connection of the coupling portion of the guide memberto the coupling portion of the pedicle screw. The alignment member isconnected to the offset member. The alignment member is operable foralignment of the connecting screw of the vertebral stabilizationassembly with a portion of the pedicle screw of the vertebralstabilization assembly.

[0038] In one aspect, the coupling portion of the guide member isoperable to couple with the coupling portion of the pedicle screw suchthat the offset member extends in a predetermined direction relative tothe coupling of the coupling portion of the guide member to the couplingportion of the pedicle screw. While in other aspects, the offset memberis further provided with a first end and a second end, and wherein thefirst end of the offset member is connected to the coupling portion andwherein the second end of the offset member is coupled to the alignmentmember.

[0039] In one aspect, the offset member is positionable relative to thecoupling of the coupling portion with the end portion of the pediclescrew. While in other aspects, the offset member extends from thecoupling portion adjacent a shaft portion of the pedicle screw.

[0040] In one aspect, the coupling portion of the guide member couplesto the coupling portion of the pedicle screw such that the offset memberpositions the alignment member connected to the offset membersubstantially aligned adjacent a portion of the pedicle screw. In yetanother aspect, the alignment member substantially aligns adjacent tothe engaging portion of a shaft of the pedicle screw. While yet in otheraspects, the alignment member substantially aligns adjacent an openingon the shaft of the pedicle screw. In yet another aspect, the alignmentmember provides alignment for threadingly taping the vertebra adjacentthe opening in the pedicle screw.

[0041] In one aspect, the alignment member provides alignment forattachment of the connecting screw of the vertebral stabilizationassembly to the pedicle screw. In other aspects, the alignment member isfurther defined as tubular member having a first end, a second end and aopening extending through the tubular member from the first end to thesecond end. While in yet other aspects, the opening extending throughthe tubular member is provided with a diameter sufficient to receive theconnecting screw of the vertebral stabilization assembly through theopening in the tubular member for alignment with an engaging portion ofa shaft of the pedicle screw of the vertebral stabilization assembly.

[0042] In another aspect, the present invention provides a vertebralstabilization assembly having dual pedicle screws including a firstpedicle, a second pedicle screw and a connecting screw. The firstpedicle screw has a shaft provided with a threaded portion operable forthreading engagement of the first pedicle screw with a first vertebra.The shaft of the first pedicle screw has an engaging portion.

[0043] The second pedicle screw has a shaft provided with a threadedportion operable for threading engagement of the second pedicle screwwith the first vertebra, the shaft of the second pedicle has an engagingportion. The connecting screw has a first end and a shaft, the first endof the connecting screw is adapted to be received by the engagingportion of the first pedicle screw. The shaft of the connecting screw isadapted for connection to the engaging portion of the second pediclescrew.

[0044] In yet another aspect, the present invention provides a methodfor stabilizing a lower vertebra and an upper vertebra from an anteriorside of the vertebrae using a vertebral stabilization assembly. Themethod includes inserting a first pedicle screw into the lower vertebrathrough a pedicle and a vertebral body of the lower vertebra from aposterior side of the lower vertebra. The pedicle screw includes a shaftprovided with a threaded portion operable to threadingly engage thelower vertebra. The shaft of the first pedicle screw has an engagingportion operable to receive a first connecting screw. The shaft of thefirst pedicle screw having a coupling portion operable to couple with aguide member of the vertebral stabilization assembly.

[0045] The method includes inserting a second pedicle screw into anupper vertebra through a pedicle and a vertebral body of the uppervertebra from a posterior side of the upper vertebra. The second pediclescrew includes a shaft provided with a threaded portion operable tothreadingly engage the upper vertebra. The shaft of the second pediclescrew has an engaging portion operable to receive a second connectingscrew. The shaft to the second pedicle screw has a coupling portionoperable to couple with a guide member of the vertebral stabilizationassembly. The method further includes locating the coupling portion ofthe shaft of the first pedicle screw from an anterior side of the lowervertebra.

[0046] The method includes coupling the guide member to the couplingportion of the shaft of the first pedicle screw from the anterior sideof the lower vertebra. The method further provides for inserting a lowerconnecting screw through the anterior side of the lower vertebra usingthe guide member. The lower connecting screw includes a first endadapted to be received by the engaging portion of the first pediclescrew and a second end adapted to reside outside the lower vertebra onan anterior side of the lower vertebra.

[0047] The method includes locating the coupling portion of the shaft tothe second pedicle screw from an anterior side of the upper vertebra.The method provides for coupling the guide member to the couplingportion of the shaft to the second pedicle screw from the anterior sideof the upper vertebra. The method further includes inserting an upperconnecting screw through the anterior side of the upper vertebra usingthe guide member. The upper connecting screw includes a first endadapted to be received by the engaging portion of the second pediclescrew and a second end adapted to reside outside the upper vertebra onthe anterior side of the upper vertebra.

[0048] The method also provides for connecting the second end of thelower connecting screw of the lower vertebra to the second end of theupper connecting screw of the upper vertebra. In one aspect, the firstand second pedicle screws are posteriorly placed on the right side ofthe lower and upper vertebra, respectively, and wherein the lower andupper vertebra are further defined as a lower and upper lumbar vertebra.In another aspect, the first and second pedicle screws are posteriorlyplaced on the right side of the lower and upper vertebra, respectively,and wherein the lower and upper vertebra are further defined as a lowerand upper thoracic vertebra.

[0049] In one aspect, the present invention is directed to a method ofanterior vertebral stabilization including placing from the patient'santerior the pedicle screw such that a portion of the pedicle screw isstabilized in a pedicle portion of the vertebra.

[0050] In one aspect, the first pedicle screw is further provided with acannulated shaft having a passageway extending from a first end to asecond end of the first pedicle screw and wherein locating the couplingportion of the shaft of the first pedicle screw from the anterior sideof the lower vertebra further provides for extending a tool operable todrill through a portion of the lower vertebra through the passageway ofthe shaft of the first pedicle screw and drilling the portion of thelower vertebra such that the tool extends at least partially through theanterior side of the lower vertebra.

[0051] In one aspect, the second pedicle screw is further provided witha cannulated shaft having a passageway extending from a first end to asecond end of the second pedicle screw and wherein locating the couplingportion of the shaft of the second pedicle screw from the anterior sideof the upper vertebra further includes extending the tool operable todrill through a portion of the upper vertebra through the passageway ofthe shaft of the second pedicle screw and drilling the portion of theupper vertebra such that the tool extends at least partially through theanterior side of the upper vertebra.

[0052] In other aspects, coupling the guide member to the first andsecond pedicle screws further includes threadingly coupling the guidemember to the coupling portion of the shaft of the first and secondpedicle screws. In another aspect, coupling the guide member to thefirst and second pedicle screws further includes matingly coupling theguide member to the coupling portion of the shaft of the first andsecond pedicle screws.

[0053] In one aspect, inserting the lower connecting screw furtherincludes positioning the lower connecting screw in alignment with theengaging portion of the first pedicle screw utilizing an alignmentmember of the guide member and threading the lower connecting screwthrough anterior side of the lower vertebra.

[0054] In one aspect, positioning the lower connecting screw inalignment with the engaging portion of the first pedicle screw furtherincludes receiving the lower connecting screw by the alignment member ofthe guide member, the guide member adapted to position the alignmentmember connected thereto the guide member substantially aligned adjacentthe engaging portion of the first pedicle screw.

[0055] In other aspects, inserting the upper connecting screw furtherincludes positioning the upper connecting screw in alignment with theengaging portion of the second pedicle screw utilizing the alignmentmember of the guide member and threading the upper connecting screwthrough anterior side of the upper vertebra.

[0056] In one aspect, positioning the upper connecting screw inalignment with the engaging portion of the second pedicle screw furtherincludes receiving the upper connecting screw by the alignment member ofthe guide member, the guide member adapted to position the alignmentmember connected thereto the guide member substantially aligned adjacentthe engaging portion of the second pedicle screw.

[0057] In another aspect, connecting the upper connecting screw to thelower connecting screw further includes, providing a connecting memberhaving a first end and a second end, connecting the second end of thelower connecting screw to the first end of the connecting member andconnecting the second end of the upper connecting screw to the secondend of the connecting member.

[0058] In yet another aspect, the connecting member is a plate andwherein the second end of the lower connecting screw receives the firstend of the plate and wherein the second end of the upper connectingscrew receives the second end of the plate.

[0059] In yet another aspect, the connecting member is a bracket andwherein the second end of the lower connecting screw receives the firstend of the bracket and wherein the second end of the upper connectingscrew receives the second end of the bracket. While in other aspects,the connecting member is a rod and wherein the second end of the lowerconnecting screw connects to the first end of the rod and wherein thesecond end of the upper connecting screw connects to the second end ofthe rod.

[0060] The pedicle screw of the present invention advantageouslyprovides for posterior placement of the pedicle screw through a pedicleportion of the vertebra for secure attachment of the pedicle screw tothe vertebra. The cannulated shaft of the pedicle screw is adapted toreceive a drill bit there through such that the drill bit may be causedto drill through to the anterior side of the vertebra for easilylocating the shaft of the pedicle screw. Another advantage of thepresent invention is that the pedicle screw is adapted for posteriorplacement through a pedicle portion of the vertebra for maximumstabilization. The connecting screw of the vertebral stabilizationassembly is adapted to engage the engaging portion provided on the shaftof the pedicle screw to further promote a stable engagement of thevertebral stabilization assembly.

[0061] Yet another advantage of the present invention is that theengagement of the engaging portion of the shaft of the pedicle screwwith the connecting screw prevents the pedicle screw or the connectingscrew from moving or backing out of the vertebra since the connectingscrew and pedicle screw are connected to one another.

[0062] Another advantage to the present invention is that the addedstability of the pedicle screw posteriorly placed and connected to theconnecting screw anteriorly insures for maximum stabilization andattachment of the connecting member and thus greater vertebralstabilization. Another advantage to the present invention is that thepedicle screw may be percutaneously placed by making only a smallposterior incision and thus overcoming the disadvantages associated withposterior fusion requiring large posterior muscle dissection and theproblems associated therewith. For this reason, the present invention issafer for the patient.

[0063] Anterior stabilization via connection to posteriorly placedpedicle screws has numerous advantages including significantly reducingthe total time required for the surgical procedure. Avoidance of theradical muscle dissection required for posterior connection andstabilization is one factor in reducing the time to perform the surgeryto about 2.5 hours versus the 5 to 7 hours such a procedures ordinarilyrequires. Thus, anterior stabilization via connection to posteriorlyplaced pedicle screws provides numerous advantages over prior vertebralstabilization systems and methods.

[0064] As well as being placed percutaneously, the pedicle screw may bepositioned so that a head of the pedicle screw is substantially flushwith the surface bone of the vertebra. Such placement further reducesinterference with back muscles and associated problems and presentsanother advantage according to one aspect of the present invention.

[0065] Another advantage is that the present invention allows for thedrill bit to be disposed within the cannulated portion of the shaft ofthe pedicle screw for only minor penetration of the surface of theanterior side of the vertebra to avoid the risk of damage to soft tissueadjacent the anterior of the vertebra.

[0066] Another advantage of the present invention is that the guidemember allows for alignment of the connecting screw with the engagingportion of the pedicle screw without the necessity for time-consumingand inaccurate x-rays, MRI's, or other similar scanning or locatingdevices.

[0067] Another advantage of the present invention is that the methodprovides for placement of the vertebral stabilization assembly on ananterior side of the vertebrae eliminating many of the problems inherentin posterior fusion. Furthermore, elimination of the posterior fusionsubstantially reduces the amount of time required to perform thestabilization procedure according to the present invention.

[0068] Another advantage of the present invention is that by posteriorplacement of the pedicle screw in the pedicle portion of the vertebraand anterior stabilization via the connecting screw, the vertebralstabilization assembly of the present invention provides improvedstabilization about a point central to the vertebral body versus aboutposterior or anterior edges of the vertebra. Thus, the present inventioncentrally distributes the stabilization pressures, tensions, weight, andstress as opposed to focusing the stabilization pressures about theouter edges of the vertebra. The central stabilization promotes improvedstabilization of the vertebrae and improved fusion of the vertebrae.

[0069] In yet another aspect, the present invention provides a vertebralstabilization assembly having dual pedicle screws for placement in afirst vertebra including a first pedicle screw, a second pedicle screwand a connecting screw. The first pedicle screw has a shaft providedwith a threaded portion operable for threading engagement of the firstpedicle screw with the first vertebra. The shaft of the first pediclescrew has an engaging portion.

[0070] The second pedicle screw has a shaft provided with a threadedportion operable for threading engagement of the second pedicle screwwith the first vertebra, the shaft of the second pedicle screw has anengaging portion. The connecting screw has a first end and a shaft, thefirst end of the connecting screw is adapted to be received by theengaging portion of the first pedicle screw. The shaft of the connectingscrew is adapted for connection to the engaging portion of the secondpedicle screw.

[0071] In one aspect, the engaging portion of the second pedicle screwis defined as a threaded opening operable for the connecting screw toextend through and further operable to secure a portion of the shaft ofthe connecting screw.

[0072] In another aspect, a fixation tool is provided for placement ofthe first and second pedicle screws in the first vertebra so as to alignthe first and second pedicle screws for connection by the connectingscrew. The fixation tool includes a first alignment member disposedadjacent a second alignment member, a third alignment member is offsetrelative to the first and second alignment members. The first and secondalignment members of the fixation tool provide alignment for positioningthe first and second pedicle screws in the vertebra. The third alignmentmember of the fixation tool aligns the connecting screw for couplingwith the first and second pedicle screws.

[0073] Other objects, features, and advantages of the present inventionwill be apparent to those skilled in the art from the following detaileddescription when read in conjunction with the accompanying drawings andappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0074] For a more complete understanding of the present invention andthe advantages thereof, reference is now made to the following briefdescription, taken in connection with the accompanying drawings anddetailed description, wherein like reference numerals represent likeparts, in which:

[0075]FIG. 1 is a perspective view of a vertebral stabilization assemblyillustrated partially in phantom and shown stabilizing an upper andlower vertebra according to one aspect of the present invention;

[0076]FIG. 2 is a perspective view of the vertebral stabilizationassembly, as shown in FIG. 1, constructive in accordance with thepresent invention;

[0077]FIG. 3 is a side view of a connecting member constructed inaccordance with one aspect of the present invention;

[0078]FIG. 3A is a side view of yet another aspect of the connectingmember of the present invention;

[0079]FIG. 3B is a side view of one aspect of a connecting screw shownwith the connecting member attached to the connecting screw by a nut;

[0080]FIG. 4 is a side elevational view of a pedicle screw according toone aspect of the present invention;

[0081]FIG. 5 is a top plan view of the pedicle screw, illustrated inFIG. 4, shown posteriorly positioned in a lumbar vertebra in accordancewith the present invention;

[0082]FIG. 6 is a perspective view of a guide member according to oneaspect of the present invention for aligning a connecting screw shown inphantom;

[0083]FIG. 7 illustrates alignment of the connecting screw utilizing theguide member for attachment of the connecting screw to the pedicle screwpositioned within the lumbar vertebra, as shown in FIG. 5, according toone aspect of the present invention;

[0084]FIG. 8 illustrates a left side posterior positioning of thepedicle screw and alignment of the connecting screw utilizing the guidemember according to yet another aspect of the present invention;

[0085]FIG. 9 is a top plan view of other aspects of the guide member andthe pedicle screw shown connected in accordance with yet another aspectof the present invention;

[0086]FIG. 10 illustrates alignment of the connecting screw utilizingthe guide member, as shown in FIG. 9, for attachment of the connectingscrew to the pedicle screw positioned within the lumbar vertebraaccording to one aspect of the present invention;

[0087]FIG. 11 is a perspective view illustrating yet another aspect ofthe connection of the pedicle screw with the guide member constructed inaccordance with the present invention;

[0088]FIG. 12 is a flow chart illustrating a method for stabilizingvertebrae from the anterior side of the vertebrae utilizing thevertebral stabilization assembly according to another aspect of thepresent invention;

[0089]FIG. 13 is a perspective view illustrating yet another aspect ofthe pedicle screw provided with a shaft having a reinforced portion;

[0090]FIG. 14 is a perspective view of another aspect of the pediclescrew illustrating the shaft with at least a first groove and a flatsurface on a distal end of the shaft constructed in accordance with thepresent invention;

[0091]FIG. 15 is a cross-sectional view of the shaft of the pediclescrew illustrated in FIG. 14 taken along line 15-15 thereof;

[0092]FIG. 16 is a perspective view of a cap according to one aspect ofthe present invention for attachment near the distal end of the pediclescrew;

[0093]FIG. 17 is a perspective view of one aspect of a tool forconnection near the distal end of the pedicle screw constructed inaccordance with the present invention; and

[0094]FIG. 18 is a perspective view of yet another aspect of the toolfor use with the vertebral stabilization assembly of the presentinvention shown connecting to the connecting screw;

[0095]FIG. 19 is a top plan view of a bore screw according to one aspectof the present invention shown obliquely disposed in the vertebra;

[0096]FIG. 20 is a top plan view of an indicator constructed inaccordance with one aspect of the present invention disposed in a boreopening of the vertebra;

[0097]FIG. 21 is a top plan view of the pedicle screw for anteriorplacement according to yet another aspect of the present invention shownwith a distal end of the pedicle screw anchored in the pedicle portionof the vertebra;

[0098]FIG. 22 illustrates the guide member of the vertebralstabilization assembly attaching adjacent a head portion of theanteriorly placed pedicle screw according to one aspect of the presentinvention;

[0099]FIG. 23 is a top plan view of another aspect of the engagingportion of the pedicle screw of present invention for attachment to theconnecting screw at various angles;

[0100]FIG. 24 is a perspective view of one aspect of the pedicle screwof the provided with non-continuous threads;

[0101]FIG. 25 is a top view of one aspect of the present inventionillustrating placement of dual pedicle screws in the vertebra utilizinga fixation tool;

[0102]FIG. 26 is a top plan view of one aspect of dual pedicle screwsinvention illustrated anteriorly placed and connected to the connectingscrew; and

[0103]FIG. 27 is a top plan view according to one aspect of the presentinvention illustrating a connecting screw extending across the vertebraand connected to one or dual pedicle screws.

DETAILED DESCRIPTION OF THE INVENTION

[0104] It should be understood at the outset that although an exemplaryimplementation of the present invention is illustrated below, thepresent invention may be implemented using any number of techniques,whether currently known or in existence. The present invention should inno way be limited to the exemplary implementations, drawings, andtechniques illustrated below, including the exemplary design andimplementation illustrated and described herein.

[0105]FIG. 1 illustrates one aspect of the vertebral stabilizationassembly 10 constructed in accordance with the present invention. Thevertebral stabilization assembly 10 is an innovative device forstabilizing a plurality of vertebrae of the spine. The vertebralstabilization assembly 10 includes a first pedicle screw 12 and a secondpedicle screw 14. The first pedicle screw includes a shaft 16 providedwith a threaded portion 18. The threaded portion 18 of the shaft 16 isoperable for threading engagement of the first pedicle screw 12 with afirst vertebra 20. The shaft 16 of the pedicle screw 12 further includesan engaging portion 22.

[0106] The second pedicle screw 14 is substantially similar to the firstpedicle screw 12 in that the second pedicle screw 14 includes a shaft 30substantially similar to the shaft 16 of the first pedicle screw 12. Theshaft 16 and 30 of the first and second pedicle screws 12 and 14,respectively, are substantially cylindrical members. The shaft 30 of thesecond pedicle screw 14 is similarly provided with a threaded portion 32similar to the threaded portion 18 provided on the shaft 16 of the firstpedicle screw 12. The threaded portion 32 of the shaft 30 is operablefor threading engagement of the second pedicle screw 14 with a secondvertebra 34. The shaft 30 of the first pedicle screw 14 is provided withan engaging portion 36.

[0107] The shafts 16 and 30 of the first and second pedicle screws 12and 14 are of appropriate length to sufficiently anchor the first andsecond pedicle screws 12 and 14 in the first and second vertebra 20 and34, respectively. The threaded portions 18 and 32 of the first andsecond pedicle screws 12 and 14 may be threads similar to those onordinary screws and extending a distance from the shafts 16 and 30sufficient to promote optimum anchoring of the first and second pediclescrews 12 and 14 within the first and second vertebra 20 and 34,respectively. The first and second pedicle screws 12 and 14 areconstructed of a rigid material such as, but not limited to, steel,metal, or metal alloys, polymeric material, or a variety of othersubstantially rigid materials adapted to promote rigid engagement of thefirst and second pedicle screws 12 and 14 to the first and secondvertebra 20 and 34, respectively.

[0108] The vertebral stabilization assembly 10 is further provided witha first connecting screw 40 and a second connecting screw 42. The firstand second connecting screws 40 and 42 are substantially cylindricalmembers and may be constructed from materials similar to that of thefirst and second pedicle screws 12 and 14, such as, but not limited to,titanium, steel, metal or other metal alloys, substantially rigidpolymeric material or a variety of other rigid metallic materialsadapted and suitable for these purposes. The first connecting screw hasa first end 44 adapted to be received by the engaging portion 22 on theshaft 16 of the first pedicle screw 12. The second connecting screw 42has a first end 46 adapted to be received by the engaging portion 36 ofthe shaft 30 of the first pedicle screw 14.

[0109] The vertebral stabilization assembly 10 further includes aconnecting member that has a first end 52 and a second end 54. The firstend 52 of the connecting member 50 is connected to the first connectingscrew 40 that is positionable in the first vertebra 20. The second end54 of the connecting member 50 is connected to the second connectingscrew 42 positionable in the second vertebra 34 for stabilization of thefirst vertebra 20 and the second vertebra 34. The connecting member 50may be constructed from a variety of materials similar to that of thefirst and second pedicle screws 12 and 14 such as, but not limited to,titanium, steel, metal, or other metal alloys, rigid polymeric material,or other rigid materials suitable for stabilization of the first andsecond vertebra 20 and 34 by connection to the first and secondconnecting screws 40 and 42.

[0110]FIG. 2 illustrates the vertebral stabilization assembly 10,substantially as shown in FIG. 1, with the first and second vertebra 20and 34 removed from the illustration for the purpose of furtherdescribing the present invention. It can be seen that the first andsecond pedicle screws 12 and 14 are provided with a head 60 and 62,respectively. The heads 60 and 62 of the first and second pedicle screws12 and 14 may be configured to receive a tool, such as, but not limitedto, a standard flat or a Phillips-head screw driver, Allen or otherwrench connection, or a variety of male to female or female to maletemporary interconnections for threadingly engaging the first and secondpedicle screws 12 and 14 into the first and second vertebra 20 and 34.

[0111] In other embodiments (not shown) the heads 60 and 62 of the firstand second pedicle screws 12 and 14 may be configured unlike the head ofthe standard screw and instead unitarily formed, for example,rectangularly from the shaft 16 and 30 for mating engagement with aunique tool adapted to receive the rectangularly-formed shaft.

[0112] It will be appreciated that a variety of constructions andconfigurations of the heads 60 and 62 of the first and second pediclescrews 12 and 14 will readily suggest themselves to one of ordinaryskill in the art and may be provided in numerous configurations suchthat a tool may be attached temporarily to the heads 60 and 62 forimparting a rotation upon the first and second pedicle screws 12 and 14.

[0113] In the present illustration, the engaging portion 22 of the shaft16 can be more easily seen as adapted to receive the first end 44 of thefirst connecting screw 40. The engaging portion 22 of the shaft 16 is athreaded opening formed in the shaft 16 of the first pedicle screw 12and adapted to receive a threaded first end 44 of the first connectingscrew 40. In this manner the first connecting screw 40 threadinglyengages the engaging portion 22 to achieve a rigid locking connectionbetween the first pedicle screw 12 and the first connecting screw 40.

[0114] In other embodiments (not shown) the engaging portion 22 may be atension connection opening in the shaft 16 for receiving and engaging ina tensioning fashion the first end 44 of the first connecting screw 40.In yet other embodiments (not shown) the engaging portion 22 may be alocking assembly adapted to receive the first end 44 of the firstconnecting screw 40 and lock into place upon insertion. The lockingengagement of the engaging portion 22 may be accomplished in a varietyof manners including a keyed design of the engaging portion 22 such thatwhen the first end 44 of the first connecting screw 40 is inserted intothe engaging portion 22 it is locked into place upon rotation of thefirst connecting screw 40.

[0115] Yet in other embodiments (not shown), the engaging portion 22 maybe a modification to the outer surface of the shaft 16 of the firstpedicle screw 12 such that the first end 44 of the first connectingscrew 40 may be adapted to receive the engaging portion 22 of the shaft16 within an opening in the first end 44 of the first connecting screw40. In this manner the locking or tensioning mechanism may be retainedby the first end 44 of the first connecting screw 40 for engaging thefirst connecting screw 40 with the first pedicle screw 12.

[0116] A number of other connections including spring, ball, or othertensioning connections, as well as, threading, locking, and other matingconnections for engaging the first end 44 of the first connecting screw40 with the engaging portion 22 of the shaft 16 of the first pediclescrew 12 will readily suggest themselves to one of ordinary skill in theart and are within the spirit and scope of the present invention. Itwill be appreciated that the engaging portion 36 of the shaft 30 of thesecond pedicle screw 14 may be constructed substantially identical tothe engaging portion 22 of the shaft 16 of the first pedicle screw 12.For purposes of brevity no further discussion of the engaging portion 36is deemed necessary to enable one of ordinary skill in the art on thevariety of means for engaging the first and second connecting screw 40and 42 with the first and second pedicle screw 12 and 14 in light of thediscussion regarding the engaging portion 22 of the first pedicle screw12.

[0117] The first connecting screw 40 is constructed substantiallysimilar to the second connecting screw 42 and for this reason, only thefirst connecting screw 40 will be discussed and described for purposesof brevity. The first connecting screw 40 is connected to the connectingmember 50 near a second end 64 of the first connecting screw 40. Theconnection of the first connecting screw 40 to the connecting member 50may be accomplished in a variety of manners such as, as shown in thepresent illustration, by providing a threaded portion on the second end64 of the first connecting screw 40.

[0118] In this manner, a coupling 70 may be coupled to the second end 64of the first connecting screw 40 and attached using a standard nutthreadingly engaged with the threaded portion 66 of the second end 64 ofthe first connecting screw 40. The coupling portion 70 may be providedwith an offset member 74 adapted to receive a rod 76. The offset member74 thereby tensions the portion of the rod 76 extending through theoffset member 74 for rigid engagement of the rod 76 to the coupling 70.

[0119] The tensioning engagement of the rod 76 by the offset member 74may be accomplished, by providing a screw (not shown), or othertension-imparting structure, threaded through the offset member 74 andinto contact with the portion of the rod 76 extending through the offsetmember 74. The use of the coupling 70 and the rod 76 is a simple anduseful design, according to one aspect, of the connecting member 50 forstabilization of the first and second vertebrae 20 and 34 via the firstand second connecting screws 40 and 42.

[0120] It should be appreciated, however, that the connecting member 50may be accomplished utilizing a variety of other structural connectionsto the first and second connecting screws 40 and 42. For example, in oneembodiment (not shown), an opening may extend through the second end 64of the first connecting screw 40. The opening of sufficient diameter toreceive the rod 76 there through the opening in the second end 64 of theconnecting screw 40. A tensioning connection, such as a screw or a nutmay be utilized to tensionally engage the rod thereto the second end 64of the first connecting screw 40. Other configurations of the coupling70 may be utilized for these purposes and are within the spirit andscope of the present invention and will readily suggest themselves toone of ordinary skill in the art.

[0121]FIG. 3 illustrates a side view of another aspect of the connectingmember 50 of the vertebral stabilization assembly 10 of the presentinvention. In this aspect the connecting member 50 is a bracket 90having a first opening 92 and a second opening 94. The bracket 90, aswith the various aspects of the connecting member 50, may be constructedfrom a variety of substantially rigid materials such as titanium, steel,metal or metal alloys, rigid polymeric material and other substantiallyrigid materials which may be utilized for these purposes.

[0122] The bracket 90 is a substantially flat plate provided with thefirst and second openings extending there through for receiving thefirst and second connecting screws 40 and 42. In this manner, the secondend 64 of the first connecting screw 40 may be cause to extend throughthe first opening 92 of the bracket 90. The nut or other similar device72 can then be threadingly engaged about the threaded portion 66 andcaused to rigidly engage the bracket 90 to the second end 64 of thefirst connecting screw 40. Similarly, the second opening 94 may beadapted to receive the second connecting screw 42 for attachmentthereto.

[0123] The symmetrical nature of the vertebral stabilization andassembly 10 lends itself to stabilization of a plurality of vertebrae.That is, the first and second pedicle screws 12 and 14 are substantiallysimilar, as are the first and second connecting screws 40 and 42. Thus,while only a first and second pedicle screws 12 and 14 and a first andsecond connecting screws 40 and 42 are shown, the present inventioncontemplates stabilization of two or more vertebrae and is well suitedfor these purposes. In other embodiments (not shown) a third, fourth, ormore pedicle screws may be utilized for engagement of a third, fourth,or more connecting screws for stabilization of a plurality of vertebrae.As such, the connecting member 50, or the bracket 90, shown in FIG. 3,will be provided having appropriate length or with the appropriatenumber of openings to receive each of the connecting screws forstabilizing the desired number of vertebrae.

[0124] One advantage of the vertebral stabilization assembly 10 of thepresent invention is that the connecting member fifty, whether utilizingthe bracket 90 or the coupling 70 with the rod 76 (see FIG. 2) isadapted for connection on the anterior or front side of the vertebrae.The connecting member 50 according to the present invention has a lowprofile and thus minimizes the interference with soft tissue within theanterior of the patient.

[0125] Another advantage of the present invention is that the firstpedicle screw 12 engaging the first connecting screw 40 provides formaximum stabilization in the vertebra 20. As such secure attachment tothe vertebra 20 is optimized and greater stabilization can beaccomplished by the innovations provided according to the presentinvention. Furthermore, the first pedicle screw 12 so connected to thefirst connecting screw 40 has the effect of inhibiting the first pediclescrew 12 from backing out of the vertebra 20, as well as preventing thefirst connecting screw 40 from backing out of the vertebra 20 as well.

[0126]FIG. 3A illustrates another aspect of the connecting member 50that is similar to the bracket 90, illustrated in FIG. 3. In this aspectthe bracket 90 is provided with a single opening 96 having a first end97 and a second end 98 extending through the bracket 90. The opening 96near the first and second ends 97 and 98 are provided with a pluralityof notches 99 adapted for securely receiving a portion of a screw, suchas the second end 64 of the first connecting screw 40.

[0127] The bracket 90 is useful where the first connecting screw 40 andthe second connecting screw 42 are not substantially aligned vertically.Thus, the notches 99 are provided so that the first and secondconnecting screws 40 and 42 may be connected to the bracket 90 atvarious notches 99 on the first and second ends 97 and 98, respectively,of the bracket 90 while maintaining the bracket 90 disposed in asubstantially vertical manner while the first and second connectingscrews 40 and 42 may not be substantially vertical with respect to oneanother.

[0128]FIG. 3B illustrates another aspect of the first connecting screw40 shown attached to the connecting member 50, such as the bracket 90,using a capped bolt 104. It can be seen that the second end 64 of thefirst connecting screw 40 is provided with a notch 106 such that thebracket 90 is flush against the notch 106 of the first connecting screw40 for secure attachment thereto. A capped bolt 104 or other low-profileconnectors may be utilized advantageously so as to minimize theinterference and contact of the vertebral stabilization assembly 10 ofthe present invention with any of the soft tissue of the patient.

[0129]FIG. 4 illustrates another aspect of the present invention of thepedicle screw, such as the pedicle screw 12, for securing a connectingscrew, such as the first connecting screw 40, of the vertebralstabilization assembly 10 of the present invention. In this aspect thepedicle screw 12, as well as having the shaft 16 having the threadedportion 18 and the engaging portion 22, as previously discussed, furtherincludes a coupling portion 100 provided on the shaft 16.

[0130] The coupling portion 100 is adapted to connect a guide member(which will be discussed in greater detail with reference to FIG. 6) ofthe vertebral stabilization assembly. In one aspect the coupling portion100 may be a threaded portion on the outer surface of the shaft 16 nearthe distal end 102 of the shaft 16. The guide member may be threadinglyconnected to the coupling portion 100 about the distal end 102 of theshaft 16. In other embodiments, however, the coupling portion may be anopening provided in the distal end 102 of the shaft 16 such that aportion of the guide member may be threadingly received within theopening in the distal end 102 of the shaft 16 for threading engagementtherewith the coupling portion 100.

[0131] As previously mentioned, the engaging portion 22 of shaft 16 isoperable to receive the first connecting screw 40. The engaging portion22 in one embodiment may be provided as an opening on the shaft 16extending completely through the shaft 16. The purpose of the engagingportion 22, as previously discussed, is to provide stabilizingengagement of the first connecting screw 40 with the first pedicle screw12. As previously discussed, this rigid engagement may be provided in avariety of manners, such as, but not limited to, a locking engagement, athreading engagement, a tensioning or other rigid coupling connection ofthe first connecting screw 40 with the first pedicle screw 12 about theengaging portion 22.

[0132] Referring also to FIG. 5 a top view of a vertebra 118, such as alumbar vertebra, shown with the first pedicle screw 12 set therein. Oneadvantage of the present invention is that the first pedicle screw 12may be placed through a pedicle 120 on a posterior side 122 of thevertebra 118.

[0133] Posterior placement through the pedicle 120 of the vertebra 118provides optimum stability and anchoring of the first pedicle screw 12by threading engagement through the most rigid portions of the vertebra118. Significant problems arise when the first pedicle screw 12 is notwell anchored within the vertebra 118 and alternate placement is thenrequired. Furthermore, stabile anchoring is critical to reduce thelikelihood that the first pedicle screw 12 will back out, or comebackwards out of its placement, of the vertebra 118. The illustratedplacement of first pedicle screw 12 advantageously overcomes thedisadvantages associated with unstable attachment common with anteriorvertebral stabilization systems.

[0134] As previously mentioned, the connecting member 50 is positionableon the anterior side 124 of the vertebra 118. Thus, the vertebralstabilization assembly 10 of the present invention achieves theadvantages of anterior vertebral stabilization, since the connectingmember is positioned on the anterior side 124 of the vertebra 118, whilesimultaneously achieving the stability associated with posteriorprocedures.

[0135] The first pedicle screw 12 may be placed in the vertebra 118,substantially as shown, percutaneously or through the skin requiringonly a small incision, and avoiding the disadvantages associated withlarge, invasive posterior procedures which require significantinterference and dissection of adjacent muscles.

[0136] In yet another aspect of the present invention the pedicle screw12 may be provided with a cannulated shaft 16 such that a passageway 110extends through the shaft 16 from the head 60 to the distal end 102thereof the shaft 16. By utilizing the passageway 110 extending throughthe shaft 16 of the first pedicle screw 12, a tool (not shown) such as atap or drill bit may be placed through this cannulated portion of theshaft 16 such that the tool or drill bit enters near the head 60 of thefirst pedicle screw 12. The tool is then extended through the passageway110 towards the distal end 102.

[0137] The tool may then be utilized to drill through to the anteriorside 124 of the vertebra 118 for location of the distal end 102 of thepedicle screw 12 from the anterior side 124 of the vertebra 118. Sinceonly a small distance must be drilled, there is minimal risk to softtissue or blood vessels. Furthermore, once the tool penetrates theanterior side 124 of the vertebra 118, the surgeon should be able tosense the reduced resistance and friction on the tool. Furthermore, thetool may be provided with stops or a drill bit may be cannulated toprevent extension of the drill beyond the anterior side 124 of thevertebra 118.

[0138] In the present embodiment right side 126 placement of the firstpedicle screw 12 is preferable to avoid soft tissue injuries to thepatient's anterior caused by penetration of the drill bit through theanterior side 124 of the vertebra 118 via the passageway 110 of thefirst pedicle screw 12. Anatomically, fragile soft tissue and bloodvessels are positioned adjacent the right side 126 on the anterior side124 of the vertebra 118. By using any number of surgical retractiontechniques, these blood vessels may be held toward the right side 126 ofthe anterior side 124 of the vertebra 118. As such, the right side 126placement of the first pedicle screw 12 represents the most efficient,as well as safest, placement for utilizing the first pedicle screw 12 inaccordance with the present invention. In some instances, however, leftside 128 placement of the first pedicle screw 12 in the vertebra 118will be necessary. Left side 128 placement of the first pedicle screw 12will be discussed in greater detail with reference to FIG. 8.

[0139]FIG. 6 illustrates yet another aspect of the present invention ofa guide member 150. The guide member 150 includes a coupling portion 152an offset member 154 and an alignment member 156. The coupling portion152 is operable to couple with the coupling portion 100 of the firstpedicle screw 12 (see FIG. 4). The offset member 154 is connected to thecoupling portion 152. The offset member 154 extends from the couplingportion 152 relative to the connection of the coupling portion 152 tothe coupling portion 100 of the first pedicle screw 12. The alignmentmember 156 is connected to the offset member 154. The alignment member156 is operable for alignment of the connecting screw, such as the firstconnecting screw 40, with a portion of the first pedicle screw 12, suchas the engaging portion 22.

[0140] The guide member 150 may be constructed from a variety ofmaterials such as, but not limited to, titanium, steel, metal or othermetal alloys, a substantially rigid polymeric material, aluminum orother substantially rigid materials sufficient for these purposes. Thecoupling portion 152 is provided with a first end 160 and a second end162. The first end 160 of the coupling portion 152 may be threaded forthreading engagement to the coupling portion 100 of the first pediclescrew 12.

[0141] It should be appreciated, however, that a number of connectingmethods may be utilized to accomplish the connection of the first end160 of the coupling portion 152 to the coupling portion 100 of the firstpedicle screw 12. For example, the first end 160 may be shaped so as tobe substantially rectangular or other geometric shape about a portion ofthe first end 160 such that a similarly geometrically configured openingin the coupling portion 100 in the distal end 102 of the first pediclescrew 12 is adapted to receive the first end 160 of the coupling portion152. Other locking or tensioning engagements of the first end 160 of thecoupling portion 152 to the coupling portion 100 of the first pediclescrew 12, as well as a variety of other methods for achieving thisattachment, will readily suggest themselves to one of ordinary skill inthe art and are within the spirit and scope of the present invention.

[0142] The second end 162 of the coupling portion 152 is attached to theoffset member 154. The attachment of the coupling portion 152 to theoffset member 154 may be of a connecting, such as threading ortensioning or locking connection, or may be accomplished by a welded orbonded connection of the second end 162 of the coupling portion 152 tothe offset member 154. Although welding or bonding engagements ofvarious components of the vertebral stabilization assembly 10 of thepresent invention are preferable, it should be appreciated that bondingor other gluing or tacking materials may be used for this connection andsatisfactory for these purposes.

[0143] The offset member 154 is shown as a substantially arcuate memberextending from the second end 162 of the coupling portion 152 to thealignment member 156. However, in other embodiments, one of which isdescribed hereinafter, the alignment member 156 may be comprised of anumber of foldable or extendable or hinging segments to promote usewithin the confinements of the patient's anterior. While the offsetmember 154 is shown as a substantially rigid arcuate member, a number ofother configurations of the offset member 154, such as a substantiallystraight member, or a stair-stepped member, as well as the offset member154 being comprised of several connectable or extendable members arecontemplated according to other aspects (not shown) of the presentinvention.

[0144] A number of configurations of the offset member 154, such asformation of a portion of the offset member 154 unitarily with thecoupling portion 152 and formation of a remaining portion of the offsetmember 154 unitarily formed with the alignment member 156 may also beutilized for these purposes. Although the offset member 154 is shown inthe preferred aspect, a variety of configurations of the offset member154 will readily suggest themselves to one of ordinary skill in the artfor positioning the alignment member 156 relative to a portion of thefirst pedicle screw 12 when the coupling portion 152 of the guide member150 is connected to the coupling portion 100 of the first pedicle screw12 and are within the spirit and scope of the present invention and willnot be discussed in further detail for the purposes of brevity.

[0145] The alignment member 156 is rigidly connected to the offsetmember 154 by welding or bonding or other similar means. However,attachment of the alignment member 156 to the offset member 154 may beaccomplished by a threading, locking or tensioning engagement and issatisfactory for these purposes. The alignment member 156 is asubstantially tubular member having a first end 164 and a second end 166and an opening 168 extending through from the first end 164 to thesecond end 166.

[0146] The alignment member 156 is provided such that the opening 168 isof a sufficient diameter to receive a drilling device 170, shown inphantom, through the opening 168 for alignment with the engaging portion22 on the shaft 16 of the first pedicle screw 12. The drilling device170 may be the a bit of a drill or other devices operative to drill anopening into vertebral bone. Thus, the alignment member 156 receives thedrilling device 170 that drills an opening properly aligned forattachment of the first connecting screw 40 to the first pedicle screw12. Thus, the guide member 150 is advantageously provided for creatingan opening aligned with the engaging portion 22 of the first pediclescrew 12.

[0147] It should be appreciated that while the alignment member 156 ofthe present aspect is illustrated as a substantially tubular memberhaving an opening 168, other embodiments the alignment member 156 maynot be a completely tubular, and instead, be provided as a guide orpositioning member for alignment of the first connecting screw 40 withthe engaging portion 22 of the first pedicle screw 12.

[0148] Numerous configurations for aligning the first connecting screw40 with the engaging portion 22 of the first pedicle screw 12 may beutilized for these purposes and will readily suggest themselves to oneof ordinary skill in the art and are within the spirit and scope of thepresent invention and will not be discussed further for purposes ofbrevity.

[0149]FIG. 7 illustrates a top view of the vertebra 118 shown with thefirst pedicle screw 12 positioned therein with the guide member 150shown attached to the first pedicle screw 12. In this view, it can beseen that the guide member 150 is a useful tool for placement of thefirst connecting screw 40 for attachment to the engaging portion 22 ofthe first pedicle screw 12. It will be appreciated that, procedurally,the first pedicle screw 12 has been percutaneously placed through theposterior side 122 of the vertebra 118. Thereafter the tool, such as thedrill, as previously discussed, is caused to drill through the anteriorside 124 of the vertebra 118 thus locating the position of the couplingportion 100 on the distal end 102 of the first pedicle screw 12.

[0150] At this point, the guide member 150 may be positioned such thatthe coupling portion 152 extends through the drilled opening on theanterior side 124 of the vertebra 118. The coupling portion 152 of theguide member 150 is then connected to the coupling portion 100 of thefirst pedicle screw 12. An innovative aspect of the pedicle screw 12 isthat the coupling portion 100 on the distal end 102 of the first pediclescrew 12 is associated with the engaging portion 22 on the shaft 16 ofthe first pedicle screw 12. The association of the coupling portion 100and engaging portion 22 of the first pedicle screw 12 is a significantadvantage of the first pedicle screw 12 according to the presentinvention. That is, this association allows for the guide member 150 tobe configured relative to this association. Thus, the coupling portion152 of the guide member 150, when coupled to the first pedicle screw 12,aligns the alignment member 156 with the engaging portion 22 on theshaft 16 of the first pedicle screw 12. Utilizing the guide member 150,several methods exist for aligning and securing the first connectingscrew 40 to the first pedicle screw 12. It may be preferable to utilizethe drilling device 170 to create an opening in the anterior side 124 ofthe vertebra 118. Thereafter, the guide member 150 may be removed andthe first connecting screw 40 disposed through the opening drilled inthe vertebra 118 and connected to the first pedicle screw 12.

[0151] In some instances, it may be beneficial for the alignment member156 to be adapted to receive the first connecting screw 40 positioned toextend through the opening 168 of the alignment member 156. The firstconnecting screw 40 may then be drilled or threaded directly into theleft side 128 of the anterior side 124 of the vertebra 118. Whether anopening is first drilled or the first connecting screw 40 is directlydrilled into the vertebra 118, the unique configuration of the guidemember 150 relative to the first pedicle screw 12 insures that the firstconnecting screw 40 will be properly aligned so as to locate theengaging portion 22 of the first pedicle screw 12 for engagingattachment thereto.

[0152] Thus, another advantage of the guide member 150 of the presentinvention is that the coupling portion 152 of the guide member 150 isoperable to couple with the coupling portion 100 of the first pediclescrew 12 such that the offset member 154 extends in a predetermineddirection relative to the coupling of the coupling portion 152 of theguide member 150 to the coupling portion 100 of the first pedicle screw12. The offset member 154 of the guide member 150 is positionablerelative to the coupling of the coupling portion 152 of the guide member150 with the coupling portion 100 of the first pedicle screw 12.

[0153] It will be appreciated that the connection of the couplingportion 152 of the guide member 150 to the coupling portion 100 of thefirst pedicle screw 12 must be a locking or fitted type connection suchthat the offset member 154 properly extends in the proper direction toposition the alignment member 156 for alignment with the engagingportion 22 of the first pedicle screw 12. Achieving the accuracynecessary to locate the engaging portion 22 of the first pedicle screw12, which will not be visible since the first pedicle screw 12 will beembedded within the vertebra 118, is preferably accomplished through theaccurate coupling connection of the coupling portion 152 of the guidemember 150 to the coupling portion 100 of the first pedicle screw 12.

[0154] It should be understood, however, that a number of other methodsof locating the engaging portion 22 of the first pedicle screw 12 foralignment with the first connecting screw 40 may be utilized. Forexample, providing indicia or markings on the head 60 of the firstpedicle screw 12 indicating the relative position of the engagingportion 22 of the first pedicle screw 12. The coupling portion 152 mayfurther include an extension (not shown) extendable through thepassageway 110 of the shaft 16 of the first pedicle screw 12. Theextension of the coupling portion 152 of the guide member 150 similarlyprovided with indicia, markings, or an alignment with the indiciaprovided on the head 60 of the first pedicle screw 12. In this manner,when the indicia are aligned, so is the alignment member 156 alignedwith the engaging portion 22 on the first pedicle screw 12.

[0155] A variety of other methods for obtaining this positioning andalignment for connecting the first connecting screw 40 to the firstpedicle screw 12 will readily suggest themselves to one of ordinaryskill in the art and are within the spirit and scope of the presentinvention and will not be discussed for purposes of brevity.

[0156]FIG. 8 illustrates an alternative left side 128 placement of thefirst pedicle screw 12 in the vertebra 118. Procedurally, numerousmethods may be utilized to determine whether the first pedicle screw 12is satisfactorily stabilized within the vertebra 118, includingelectrical stimulation to test for a desired threshold. In certaincircumstances, such as when the right side 126 placement of the firstpedicle screw 12 is ineffective to achieve the desired or requiredstability, left side 128 placement of the first pedicle screw 12 may benecessary. In this instance, the present invention may be utilized insubstantially the same manner for left side 128 placement.

[0157] The significant difference between the first pedicle screw 12utilized for right side 126 placement, as opposed to left side 128placement, is an angle 176 of the engaging portion 22 of the firstpedicle screw 12 relative to an axis extending centrally through theshaft 16, such as the passageway 110 of the first pedicle screw 12. Itcan be seen that the angle 176 of the engaging portion 22 of the firstpedicle screw 12 necessary for placement of the first connecting screw40 about the left side 128 of the anterior side 124 of the vertebra 118varies considerably depending upon whether the first pedicle screw 12 isconnected from the left side 128 or the right side 126 of the vertebra118. For this reason, a unique first pedicle screw 12 and guide member150 will be constructed for the left side 128 versus right side 126placement, such that the guide member 150, when connected to the firstpedicle screw 12, properly aligns the first connecting screw 40 basedupon which vertebral placement, and corresponding first pedicle screw 12is utilized.

[0158]FIG. 9 illustrates another aspect of the first pedicle screw 12 aswell as another aspect of the guide member 150. The vertebra 118 isshown having a midline 178 extending from the anterior side 124 to theposterior side 122 of the vertebra 118. The coupling portion 152 of theguide member 150 is shown connected to the first pedicle screw 12 on theleft side 128 of the vertebra 118 adjacent the midline 178. Aspreviously discussed, placement of the first pedicle screw 12 on theleft 128 anterior side 124 of the vertebra 118 may be preferable.

[0159] In this aspect the guide member 150 is shown having asubstantially non-arcuate offset member 154 such that the alignmentmember 156 extends angularly therefrom the offset member 154. Thecoupling portion 152 is shown as a substantially tubular member having achannel 180 extending through the coupling portion 152. The couplingportion 152 is provided with a recess 182 extending into the channel 180near the first end 160 of the coupling portion 152. Furthermore, in thisaspect, the first end 160 of the coupling portion 152 is adapted tomatingly receive the first pedicle screw 12 near the distal end 102thereof. As previously discussed, the first pedicle screw 12 is providedwith a coupling portion 100 provided, in this aspect, as an opening inthe distal end 102 of the first pedicle screw 12.

[0160] A locking screw 184 may be extended through the channel 180 fromthe second end 162 toward the first end 160 of the coupling portion 152.The locking screw 184 is provided with a head 186 having a largerdiameter than that of a shaft 188 portion of the locking screw 184. Thefirst end 160 of the coupling portion 152 is matingly connectable to thedistal end 102 of the first pedicle screw 12. The locking screw 184 ispositioned through the channel 180 until the shaft 188 portion of thelocking screw 184 couples with the coupling portion 100 of the firstpedicle screw 12.

[0161] A tool (not shown) having any standard screw driver or hex,octagonal-type or other connection, for example, may be extended downthe channel 180 and used to connect the locking screw 184 to thecoupling portion 100 of the first pedicle screw 12. The locking screw184 may be threadingly screwed into engagement with the first pediclescrew 12 or connected in other manners which are well known and willreadily suggest themselves to one of ordinary skill in the art.

[0162] In this manner, the head 186 of the locking screw 184 engages therecess 182 within the channel 180 of the coupling portion 152 therebyengaging the coupling portion 152 to the first pedicle screw 12. It willbe appreciated that the locking screw 184, the coupling portion 152 andthe guide member 150 may be provided with indicia or markings toindicate locking engagement and alignment with both the first pediclescrew 12 and the vertebra 118 since it is critical that the lockingscrew 184 couple the coupling portion 152 to the first pedicle screw 12at a particular position relative to the vertebra 118. The indicia ormarkings may include cross-hair lines, a single line or mark, an arrow,or other markings indicating a rotational position desired for achievingthis connection and location.

[0163] Such accurate positioning may be accomplished based on thethreads of the shaft 188 of the locking screw 184 corresponding tothreaded openings within the coupling portion 100 of the first pediclescrew 12. A variety of different structural attachments for obtainingthis locking connection for alignment of the guide member 150 with thefirst pedicle screw 12 such that the alignment member 156 issubstantially aligned with the engaging portion 22 on the shaft 16 ofthe first pedicle screw 12 may be utilized and are within the spirit andscope of the present invention and will readily suggest themselves toone of ordinary skill in the art.

[0164]FIG. 10 illustrates the first pedicle screw 12 placed from theright side 126 on the posterior side 122 of the vertebra 118. It will beappreciated that the exact placement and size of the first pedicle screw12 relative to the vertebra 118, as shown and disclosed, herein may beenlarged or reduced proportionately depending upon the characteristicsof the vertebra 118 and the goals of the vertebral stabilizationassembly 10. However, the first pedicle screw 12 is preferably securedin the pedicle portion of the vertebra 118 such that the distal end 102of the first pedicle screw 12 is coupleable to the guide member 150 onthe left side 128 on the anterior side 124 adjacent the midline 178 ofthe vertebra 118.

[0165] In some aspects, the guide member 150 may be provided with arotational coupling 190 such as a recess or opening in the offset member154 of the guide member 150. The rotational coupling 190 may be adaptedas an opening to receive a tool or device for obtaining leverage on theguide member 150 for rotation of the guide member 150. It will beappreciated that while the first pedicle screw 12 may be provided withindicia or other markings on the head 60 of the first pedicle screw 12for determining the location and disposition of the engaging portion 22of the first pedicle screw 12, a surgeon may have difficulty determiningfrom the posterior side 122 of the vertebra 118 the optimum location forplacement of the connecting screw, such as the first connecting screw40.

[0166] Once the patient has been rotated and the guide member 150connected to the first pedicle screw 12 on the anterior side 124 of thevertebra 118, only then will the surgeon be able to determine thepreferable placement of the first connecting screw 40 relative to thebody of the vertebra 118. In the event the first pedicle screw 12 is notaligned preferably for the first connecting screw 40, by use of therotational coupling 190, such as with a tool connected thereto, thesurgeon may rotate the guide member 150 and the first pedicle screw 12rigidly connected thereto, via the locking screw 184, to obtain theoptimum placement of the first connecting screw 40 into a desired pointin the body of the vertebra 118. In other embodiments, the guide member150 may not include the rotational coupling 190 and, as such, thisrotational alignment may be achieved by grasping and rotating the offsetmember 154 or other portions of the guide member 150.

[0167] Once this optimum positioning has been obtained by rotation usingthe rotational coupling 190 the tool coupled to the rotational coupling190 may be removed and a drill or other tool may be utilized and alignedvia the alignment member 156 for drilling an opening into the body ofthe vertebra 118 at the desired location. Thereafter, the locking screw184 and a guide member 150 may be removed for connection of the firstconnecting screw 40 to the engaging portion 22 of the first pediclescrew 12.

[0168] It will be appreciated that the locking screw 184 may beconnected in a variety of manners to the coupling portion 152 of theguide member 150 to obtain a corresponding rotation of the guide member150 with the first pedicle screw 12 for these rotational purposes whichwill readily suggest themselves to one of ordinary skill in the art andare within the spirit and scope of the present invention.

[0169]FIG. 11 illustrates another aspect of the connection of the firstpedicle screw 12 to the coupling portion 152 of the guide member 150. Aspreviously discussed above, a variety of methods exist for connectingthe coupling portion 152 with the coupling portion 100 of the firstpedicle screw 12. In the present aspect illustrated in FIG. 11, thecoupling portion 100 of the first pedicle screw 12 is a substantiallyrectangular member extending therefrom the shaft 16 of the first pediclescrew 12.

[0170] The coupling portion 152 of the guide member 150, in the presentaspect, is provided with a substantially rectangular opening 196 in thefirst end 160 of the coupling portion 152. The substantially rectangularopening 196 is sized to matingly receive the rectangular couplingportion 100 to achieve a fitted coupling there between. In this aspect,the coupling portion 100 may be provided with a threaded opening 198 onthe distal end 102 of the first pedicle screw 12. In this manner, thechannel 180 extending there through the coupling portion 152 may beprovided to guide a connecting member, such as the locking screw 184 orother engaging structure, to be threadingly received by the threadedopening 198 in the distal end 102 of the first pedicle screw 12.

[0171] In this manner, the combination of the locking mechanism, such asthe locking screw 184, as well as the rectangular configuration of thecoupling portion 100 of the first pedicle screw 12 with thesubstantially rectangular opening 196 in the first end 160 of thecoupling portion 152 promotes an accurately engaged connection of theguide member 150 with the first pedicle screw 12. It should beappreciated that in other aspects the threaded opening 198 and thechannel 180 may be eliminated and only the mating connection of therectangular coupling portion 100 of the first pedicle screw 12 with thesubstantially rectangular opening 196 of the coupling portion 152 willbe sufficient for this connection.

[0172] It will be appreciated that the configuration illustrated in thecurrent aspect promotes a sufficient engagement of the guide member 150to the first pedicle screw 12 to achieve engaging rotation of the firstpedicle screw 12 by the guide member 150 when such adjustment foralignment purposes of the first pedicle screw 12 is desirous. It shouldbe appreciated that while the coupling portion 100 of the current aspectis shown as substantially rectangular in configuration as is thesubstantially rectangular opening 196 of the coupling portion 152 of theguide member 150, a variety of other configurations such as, but notlimited to, triangular configurations, will readily suggest themselvesto one of ordinary skill in the art and are within the spirit and scopeof the present invention, as are a variety of other coupling connectionsbetween the coupling portion 152 and the first pedicle screw 12 whichmay be utilized to achieve these purposes.

[0173]FIG. 12 is a flow chart illustrating a method 200 for stabilizingan upper and lower vertebra 118A and 118B, substantially similar to thevertebra 118 illustrated in FIGS. 5 and 7, from an anterior side 124 ofthe vertebra 118A and 118B using the vertebral stabilization assembly 10in accordance with the present invention. The method includes, at ablock 202, inserting the first pedicle screw 12 into the lower vertebra118B through the pedicle 120 and into the body of the lower vertebra118B from a posterior side 122 of the lower vertebra 118B. The firstpedicle screw, as previously described above, includes the shaft 16provided with the threaded portion 18 operable to threadingly engage thelower vertebra 118B. The shaft 16 of the first pedicle screw 12 isprovided with the engaging portion 22 that is operable to receive thefirst connecting screw 40. The shaft 16 of the first pedicle screw 12further has the coupling portion 100 that is operable to couple with theguide member 150.

[0174] The method further includes, at a block 204, inserting a secondpedicle screw 14 into the upper vertebra 118A through the pedicle 120and vertebral body of the upper vertebra 118A from the posterior side122 of the upper vertebra 118A. The second pedicle screw 14 includingthe shaft 30 provided with the threaded portion 32 operable tothreadingly engage the upper vertebra 118A. The shaft 30 of the secondpedicle screw 14 provided with an engaging portion 36 operable toreceive the second connecting screw 42. The shaft 30 of the secondpedicle screw 14 having a coupling portion 100, substantially similar tothe coupling portion 100 of the first pedicle screw 12, to couple withthe guide member 150.

[0175] The first and second pedicle screws 12 and 14 are preferablyplaced on the posterior side 122 on the right side 126 of the upper andlower vertebra 118A and 118B, respectively. It will be appreciated thatin one aspect the present invention may be utilized preferably withrespect to the lumbar vertebra, while in other embodiments the presentinvention may be preferably utilized with regard to the thoracicvertebra.

[0176] At a block 206, the method includes locating the coupling portion100 of the shaft 16 of the first pedicle screw 12 from the anterior side124 of the lower vertebra 118B. As previously discussed, in one aspectthe pedicle screw 12 of the present invention may be provided with thecannulated shaft 16 having the passageway 110 extending through theshaft 16 of the first pedicle screw 12. In this aspect a tool, such as adrill operable to drill through a portion of the lower vertebra 118B,may be extended through the passageway 110 of the shaft 16 of the firstpedicle screw 12. The tool may be used to drill through a portion of thelower vertebra 118B such that the tool extends partially through theanterior side 124 at the lower vertebra 118B. Similarly, the secondpedicle screw 14 may be similarly provided with the passageway 110 forpassing the tool there through to drill through a portion of the uppervertebra 118A such that the drill extends at least partially through theanterior side 124 of the upper vertebra 118A.

[0177] At a block 208 the method includes coupling the guide member 150to the coupling portion 100 of the shaft 16 of the first pedicle screw12 from the anterior side 124 of the lower vertebra 118B. In one aspectthe coupling of the guide member may be more readily accomplished afteran opening has been drilled through to the anterior side 124 of thelower vertebra 118B. The method further includes, at a block 210,inserting the lower connecting screw, such as the first connecting screw40, through the anterior side 124 of the lower vertebra 118B using theguide member 150. As previously discussed, the guide member is a usefultool for aligning the alignment member 156 of the guide member 150 andcorrespondingly the first connecting screw 40 with the engaging portion22 of the first pedicle screw 12.

[0178] The method further provides, at a block 212, locating thecoupling portion 100 of the shaft 30 of the second pedicle screw 14 fromthe anterior side 124 of the upper vertebra 118A. The method furtherprovides, at a block 214, for coupling the guide member 150 to thecoupling portion 100 of the shaft 30 of the second pedicle screw 16 fromthe anterior side 124 of the upper vertebra 118A.

[0179] At a block 216, the method includes inserting an upper connectingscrew, such as the second connecting screw 42 through the anterior side124 of the upper vertebra 118A utilizing the guide member 150 for properalignment. The method also provides, at a block 218, for connecting theupper and lower connecting screws, such as the first and secondconnecting screws 40 and 42, to the connecting member 50 forstabilization of the upper and lower vertebra 118A and 118B.

[0180]FIG. 13 illustrates another aspect of the first pedicle screw 12having a reinforced portion 230 provided on the shaft 16. The reinforcedportion 230 of the shaft 16 provides additional structural stability forconnection of the connecting screw, such as the first connecting screw40, to the engaging portion 22 to ensure a rigid and stable connectionof the first connecting screw 40 to the first pedicle screw 12. Thereinforced portion 230 is shown having a diameter 232 that is greaterthan a diameter 234 of a first threaded portion 236 of the shaft 16. Inthis manner, it is readily apparent that the reinforced portion 230having a greater diameter 232 will provide additional structuralstability and support for connection of the first connecting screw 40with respect to the smaller diameter 234 of the first threaded portion236 of the shaft 16. The first threaded portion 236 of the shaft 16 isprovided with a plurality of threads 238 connected to and extending fromthe shaft 16 of the first pedicle screw 12. It can be seen that thediameter 232 of the reinforced portion 230 is about equal to a diameter240 measured from an outermost edge of the plurality of threads 238 ofthe first threaded portion 236.

[0181] As the first pedicle screw 12 is threadingly engaged into thepedicle portion of the vertebra, such as the first vertebra 20, thefirst threaded portion 236 will threadingly engage and retain the firstpedicle screw 12 within the first vertebra 20. In the present embodimentthe reinforced portion 230 is not provided with threads, however, inother embodiments the reinforced portion may be provided with threadssimilar to the plurality of threads 238 or threads extending less farfrom the reinforced portion 230 than the plurality of threads 238 extendfrom the first threaded portion 236 of the shaft 16. In one aspect, thediameter 232 of the reinforced portion 230 is about 6.5 millimeters.However, in other embodiments the diameter 232 of the reinforced portion230 may be greater or less than 6.5 millimeters as may be necessary toproperly engage the shaft 16 of the first pedicle screw 12 in the firstvertebra 20.

[0182] The shaft 16 of the first pedicle screw 12 is further providedwith a second threaded portion 242 having a plurality of threads 244 forengaging the first vertebra 20. In the present aspect, the diameter 232of the reinforced portion 230 is less than the diameter 246 measuredfrom an outermost edge of the plurality of threads 244 provided on thesecond threaded portion 242. As the first pedicle screw 12, of thepresent aspect, is engaged into the first vertebra 20, the firstthreaded portion 236 will threadingly engage the pedicle portion andthereafter an interior vertebral body portion of the first vertebra 20.As the reinforced portion 230 of the first pedicle screw 12 followsbehind the first threaded portion 236, the reinforced portion 230 mayhave the affect of smoothing the threading engagement within thevertebral body. For this reason, it may be advantageous to provide theplurality of threads 244 having a greater diameter 246 for providingadditional threading engagement of the first pedicle screw. In otheraspects (not shown) frictional engaging surface structure, such as smallor low profile threads, may be provided on the reinforced portion 230for frictionally engaging the inner vertebral body at the first vertebra20.

[0183] In the present aspect, the diameter 246 of the plurality ofthreads 244 may be about 7.0 millimeters to achieve additional threadingengagement of the second threaded portion 242 of the shaft 16 for stableengagement of the first pedicle screw 12 within the first vertebra 20.It will be appreciated, however, that in other aspects (not shown) thediameter 246 of the plurality of threads 244 may be of larger or smallerdiameter or may be of a similar or smaller diameter than the diameter232 of the reinforced portion 230 and be adequate for these purposes.Furthermore, in other aspects (not shown) the diameter 234 of the firstthreaded portion 236 of the shaft 16 may be the same or larger diameterthan that of the diameter 232 of the reinforced portion 230. Thereinforced portion 230 of the shaft 16 provides significant additionalstructural stability for connection of the first connecting screw 40 tothe first pedicle screw 12 via the engaging portion 22. While the lengthof the reinforced portion 230 relative to the length of the entire shaft16 of the first pedicle screw 12 is shown in relative proportionaccording to the present aspect, the reinforced portion 230, accordingto other aspects (not shown), may be of significantly greater length anddiameter or having a smaller length and diameter relative to the shaft16 of the first pedicle screw 12 and are within the spirit and scope ofthe present invention as disclosed and described herein.

[0184]FIG. 14 illustrates a perspective view of another aspect of thepedicle screw 12 wherein the shaft 16 is provided with at least a firstgroove 250 extending a distance along the shaft 16 of the first pediclescrew 12. In the present aspect, a plurality of grooves 250 are shownadjacent a plurality of raised threaded portions 252. The raisedthreaded portions 252 are provided for threadingly engaging the firstvertebra 20 for securing the first pedicle screw 12 to the firstvertebra 20. The one or more grooves 250 are provided for engaging thefirst pedicle screw 12 by a tool which will be discussed in greaterdetail hereinafter with respect to FIGS. 17 and 18. In certaincircumstances it may be useful or necessary to rigidly retain the firstpedicle screw 12 from the anterior side of the first vertebra 20, suchas when connecting the first connecting screw 40 to the first pediclescrew 12. The one or more grooves 250 provided on the shaft 16 promotesengagement of the first pedicle screw 12 by a tool near the distal end102 of the shaft 16.

[0185]FIG. 15 illustrates a cross section of the first pedicle screw 12illustrated in FIG. 14 taken along a line 15-15 thereof. In this view,the one or more grooves 250 provided on the shaft 16 of the firstpedicle screw 12 can be seen with respect to their relationship to theraised threaded portions 252. This configuration is useful for promotingengagement of a tool for connecting near the distal end 102 of the firstpedicle screw 12. Although the grooves 250 are shown as generallyrounded in configuration extending a distance along the length of theshaft 16 it will be appreciated that in other embodiments (not shown)the grooves 250 may be angular, such as rectangular or triangular inconfiguration, and having a wider or narrower width 254 which are withinthe spirit and scope of the present invention as disclosed and describedherein.

[0186] In this view, it can be seen that a number of grooves 250 such astwo or four grooves 250 may promote improved engagement by a tool of thefirst pedicle screw 12 near the distal end 102, however, any number ofgrooves 250 may be utilized and are within the spirit and scope of thepresent invention.

[0187] It will be appreciated that the configuration of the firstpedicle screw 12 illustrated having one or more grooves 250 extending adistance along the length of the shaft 16 may also be utilized withrespect to the configuration of the first and second connecting screws40 and 42. In this manner, a tool may be utilized to connect to thesecond end 64 of the first connecting screw 40 for inserting the firstconnecting screw 40 into the engaging portion 22 of the first pediclescrew 12, as well as for removal of the first connecting screw 40 fromthe engaging portion 22 of the first pedicle screw,12.

[0188] From time to time it may be necessary to remove portions of thevertebral stabilization assembly 10 of the present invention from thepatient and it will become necessary for the first connecting screw 40and the first pedicle screw 12 to be configured so as to be easilyremovable. It will be appreciated that metal tightly connectedfrequently galls or becomes frozen. In this manner, configuration of thefirst pedicle screw 12 and the first connecting screw 40 having, forexample, grooves 250 and other similar configurations, as previouslydiscussed, and utilization of a tool adapted to engage the grooves 250along the shaft 16 of the first pedicle screw 12, for example, will bebeneficial for obtaining the necessary leverage for installation andremoval purposes.

[0189]FIG. 16 illustrates a cap 260 configured to be connected near thedistal end 102 of the first pedicle screw 12. The cap 260 may beconstructed from a variety of materials, such as a rigid or non-rigidplastic or polymeric material, metallic or other materials adapted forconnection to the first pedicle screw 12 for penetration through thebody of the first vertebra 20. In the present aspect it can be seen thatthe first end 262 of the cap 260 is substantially conically shaped forpromoting penetration of the first pedicle screw 12 through the firstvertebra 20. The cap 260 is advantageously provided where the firstpedicle screw 12 is provided with a flat surface 264 on the distal end102 of the first pedicle screw 12 (see FIG. 14).

[0190] A flat surface 264 on the distal end 102 of the first pediclescrew 12 further promotes connection and engagement of a tool to thefirst pedicle screw 12 for purposes which will be discussed hereinafter.In this aspect, the cap 260 will be necessary to reduce or minimize anydamage or aggravation caused by placement of the pedicle screw to anynerves or tissue in or about the area of the first vertebra 20, such asnerves positioned near the pedicle portion of the first vertebra 20.

[0191] The cap 260 is shown as a substantially conical member having aninner surface 266 that is provided with one or more notches 268 providedon the inner surface 266 of the cap 260. The notches 268 are configuredto be tensioningly received by a recess 270 which may be provided on theshaft 16 of the first pedicle screw 12 as shown in FIG. 14. In thismanner, the notches 268 are tensioningly received by one or morerecesses 270 on the shaft 16 which retains the cap 260 sufficientlyengaged near the distal end 102 of the first pedicle screw 12, as wellas promoting easy removal of the cap 260 from the first pedicle screw12. The cap 260 may then be easily removed after placement of the firstpedicle screw 12 for attachment of the guide member 150, as well as atool for retaining and stabilizing the first pedicle screw 12 near thedistal end 102 of the first pedicle screw 12.

[0192]FIG. 17 illustrates a tool 280 constructed in accordance with oneaspect of the present invention for stabilization of the first pediclescrew 12 and the connecting screws, such as the first connecting screw40. The tool 280 is provided with a first end 282 having a handle 284adapted to be grasped by the hand of an individual. The tool 280 isprovided with a shaft 286 extending from the first end to a second end288. The shaft 286 may be of sufficient length to easily utilize thetool 280 for connection and removal of the vertebral stabilizationassembly 10 during the surgical process.

[0193] A connector 290 is provided on the second end 288 of the tool 280and configured so as to receive, for example, the shaft 16 of the firstpedicle screw 12 provided with one or more grooves 250 on the shaft 16.In this manner, the connector 290 is provided with mating notches 292adapted to be received by the grooves 250 on the shaft 16 of the firstpedicle screw 12.

[0194] Once positioned near the distal end 102 of the first pediclescrew 12, the mating notches 292 will receive and engage the firstpedicle screw 12 so that the tool 280, when rotated by the individual,will have the affect of rotating the first pedicle screw 12, or, aspreviously discussed, for stabilizing and retaining the first pediclescrew 12 while removing or installing the connecting screws, such as thefirst connecting screw 40. As previously discussed, it may be necessaryto utilize the tool 280 to stabilize the first pedicle screw 12,particularly when attempting to remove the rigid connection of the firstconnecting screw 40.

[0195] During the removal of the vertebral stabilization assembly 10,the first connecting screw 40 will likely be rigidly engaged in theengaging portion 22 of the first pedicle screw 12. When utilizing afirst tool, such as the tool 280, to connect to for removal of the firstconnecting screw 40, it may be necessary to utilize a second tool, suchas the tool 280, to engage the distal end 102 of the first pedicle screw12 to retain the first pedicle screw 12 while removing the firstconnecting screw 40. Utilization of one or more of the tools 280 may bebeneficial while installing, as well as removing the vertebralstabilization assembly 10.

[0196] Furthermore, it will be appreciated that in other aspects theconnector 290 may be provided on an electric or pneumatic device such asa drill or other apparatus.

[0197]FIG. 18 illustrates another aspect of the tool 280 and a differentaspect of the handle 284 as well as the connector 290. In this view, thehandle 284 is more easily grasped by a single hand, such as the handleof a common screw driver, and the connector 290 is configured with aplurality of flat surfaces 294, such as ordinarily found in awrench-wrench. In this manner, the first connecting screw 40 may beprovided with an opening 296 configured to receive the connector 290 forengagement of the tool 280 with the first connecting screw 40.

[0198] A number of configurations of the opening 296 on the second end64 may be utilized such as one or more grooves 250, and may be providedwith associated tools, such as the tool 280 to establish a rigidengagement of the tool 280 to the connecting screw, such as the firstconnecting screw 40, and the first pedicle screw 12. It is within thescope of the present invention that the various configurations of thefirst pedicle screw 12 and the first connecting screw 40 may beinterchanged along with the configurations of the tool 280 to promotemaximum utility for installation and removal of the vertebralstabilization assembly. For example, the grooves 250 may be provided onthe shaft 16 of the first pedicle screw 12, substantially as shown withrespect to FIGS. 14 and 15, while the first connecting screw 40 may beprovided with a wrench wrench-type opening 296 or vice versa.

[0199] In this manner, one or more configurations of tools may beutilized on one or more of the elements of the vertebral stabilizationassembly 10 and are within the spirit and scope of the present inventionas disclosed and described herein. Furthermore, it will be appreciatedthat the opening 296 provided on the first connecting screw 40 or on thedistal end 102 of the first pedicle screw 12 may be tapped and threadedopening in a standard or reverse threaded manner for engagement of, forexample, the connector 290 having a threaded connector 290 (not shown)for engagement of the tool 280 to the first connecting screw 40 or thefirst pedicle screw 12.

[0200] Also, for example, where the distal end 102 of the first pediclescrew 12 is substantially rectangularly shaped, such as in the aspectillustrated in FIG. 11, the connector 290 of the tool 280 may beconfigured to receive the rectangular distal end 102 of the firstpedicle screw 12 or a rectangularly shaped second end 64 of the firstconnecting screw 40. Many other configurations of the distal end 102 ofthe pedicle screw, such as the first pedicle screw 12, and connectingscrews, such as the first connecting screw 40, may be provided andassociated tools 280 having connectors 290 for connection thereto andwill readily suggest themselves to one of ordinary skill in the art andare within the spirit and scope of the present invention described anddisclosed herein.

[0201] Furthermore, it is within the spirit and scope of the presentinvention that the first connecting screw 40 may be provided with adouble-bolted configuration on the threaded portion 66 of the firstconnecting screw 40 and the connector 290 may be a socket-typeconnection to receive the bolt or bolts for removal of the firstconnecting screw 40 utilizing the tool 280.

[0202]FIG. 19 illustrates a bore screw 300 which may be utilizedaccording to one aspect of the present invention. The bore screw 300 maybe provided with threads (not shown) and may be placed obliquely fromthe posterior side 122 of the vertebra 118. The bore screw 300 may besized such that the diameter 302 of the bore screw 300 is sizedsubstantially similar to or smaller than the diameter of the pediclescrew, such as the first pedicle screw 12. However, it will beappreciated that in other aspects it may be advantageous for thediameter 302 of the bore screw 300 to be substantially similar in sizeto that of the first pedicle screw 12 or, in some instances, for thediameter 302 to be substantially larger.

[0203] The bore screw 300 is shown disposed in the pedicle 120 at adesirable angle extending through the vertebra 118. In this manner thebore screw 300 may be utilized to create a bore opening (not shown) thatmay be useful for placing the pedicle screw, such as the first pediclescrew 12, for placement of the pedicle screw from the anterior side 124of the vertebra 118. In such a procedure the bore screw 300 may bepercutaneously placed in the posterior 122 of the vertebra 118.Thereafter the patient may be rotated such that the anterior 124 of thevertebra 118 is exposed. The bore screw 300 may be provided with acoupling portion 308 adapted for attachment by a tool (not shown) forremoval of the bore screw 300 through the anterior 124 side of thevertebra 118.

[0204] In other aspects, the bore screw 300 may be utilized from theanterior 124 for tapping the vertebra 118. In other aspects, thecoupling portion 308 is adapted to engage the guide member 150 fordetermining alignment. For example, the guide member 150 may be attachedto the coupling portion 308 of the bore screw 300 to determine theapproximate location of the connecting screw, such as the firstconnecting screw 40, and where the second end 64 of the first connectingscrew 40 will be exposed on the anterior 124 side of vertebra 118.

[0205] Attachment of the guide member 150 to the bore screw 300 providesanother advantage of the present aspect in that it may be easilydetermined whether the bore screw 300 is placed at the appropriatelocation in the vertebra 118 or whether another placement will benecessary. This eliminates the need to place the pedicle screw, such asthe first pedicle screw 12, and then determine whether the placement isacceptable.

[0206]FIG. 20 illustrates a bore opening 310 which may have been createdby the bore screw 300, or in other embodiments may have been created bya drill or other device capable of creating an opening in the vertebra118. An indicator 312 is shown disposed in the bore opening 310. Theindicator is provided with a shaft 314 and a light 316 provided on oneend of the shaft 314. The light 316 may be a common LED (light emittingdiode) or other light-emitting device which is suitable for thesepurposes, and may include laser light or laser light-emitting diodes.

[0207] The shaft 314 may be a substantially rigid shaft of sufficientlength to extend down the length of the bore opening 310 and be operableto retain the light 316 and communicate sufficient electrical power tomaintain the light 316 with power for driving the light 316. In otheraspects, the shaft 314 may be a substantially flexible material such aswire or other flexible cording or material.

[0208] The indicator 312 is a useful device for indicating the locationof the bore opening 310 from the anterior side 124 of the vertebra 118.As previously discussed, a number of soft tissues exist on the rightside 126 on the anterior side 124 of the vertebra 118. For this reason,whether a bore screw 300 or a drill is utilized to create the boreopening 310 from the posterior side 122, it will be necessary in manycases to prevent penetration of the bore screw 300 or drill completelythrough the vertebra 118 on the anterior side 124 to prevent damage tothe soft tissues on the anterior side 124. The indicator 112 provides anopportunity once the patient has been rotated to retract the softtissues and identify the location of the bore opening 310 from theanterior side 124.

[0209] For example, the light 316 shown in the bore opening 310 will beperceptible by the surgeon from the anterior side 124 of the vertebra118. The surgeon may then drill from the anterior side 124 to completethe bore opening 310. Where the bore screw 300 is utilized, the borescrew may be provided with a light, such as the light 316, provided onthe distal end of the bore screw 300 and will be sufficient for thesepurposes. Once the light 316, whether provided on the indicator 312 orthe bore screw 300, has been identified and the bore opening has beendrilled to communicate with the anterior side 124 of the vertebra 118,the indicator 312 or bore screw 300 may then be removed from theanterior side. The indicator 314, such as when the light 316 is a highintensity LED or laser light, may be disposed near the posterior side122 or only slightly within the bore opening 310 such that the lightproduced by the light 316 projects down through the bore opening 310 andis sufficient to identify the bore opening 310 from the anterior side124 of the vertebra 118.

[0210] Furthermore, the indicator 312 may, in other aspects, be providedwith a pneumatic or hydraulically operated capability for punching orextending through the anterior side 124 of the vertebra 118 when theindicator 312 is extended through the bore opening 310, such as byutilizing a drill. In this manner, the indicator 312 may be left inplace in the bore opening 310 and after the patient has been rotatedsuch that the anterior side 124 of the vertebra 118 has been exposed,the pneumatic or hydraulically-operated indicator 312 may be activatedso as to extend through the anterior side 124 for communication into thebore opening 310.

[0211] The indicator 312 may be pulled through the anterior side 124 ofthe vertebra 118, and in instances where the shaft 314 is a flexiblematerial, it may be severed from, for example, behind the patient, foreasy removal through the anterior side 124. Where the bore screw 300 isutilized and still in place, a tool (not shown) may be connected to thecoupling portion 308 of the bore screw 300 so that the bore screw 300may be removed through the anterior side 124 of the vertebra 118. Thisis advantageous since it eliminates the rotation of the patient forremoval of the bore screw 300 or the indicator 312. The elimination of arotational procedure further reduces the time of the overall procedureand is another advantage of the present aspect of the vertebralstabilization assembly 10 invention disclosed herein.

[0212]FIG. 21 illustrates another aspect of the vertebral stabilizationassembly 10 of the present invention. In this aspect the pedicle screw,such as the first pedicle screw 12, is placed in the vertebra 118 fromthe anterior side 124. By utilizing the bore opening 310, the pediclescrew 12 may be more easily and accurately placed into the vertebra 118from the anterior side 124. Placement of the first pedicle screw 12 fromthe anterior side 124 has a number of advantages including that theangle of placement has been previously defined by the bore opening 310.This allows for selection of the first pedicle screw 12 having anengaging portion 22 provided with the appropriate angle 320 with respectto connection of the connecting screw, such as the first connectingscrew 40 (shown in phantom).

[0213] It will be appreciated that the exact angle of placement of thefirst pedicle screw 12 and resulting angle 320 with respect to theengaging portion 22 and first connecting screw 40 will be unknown untilsuch time that the first pedicle screw 12 is actually in place in thevertebra 118. By previously providing the bore opening 310, the properpedicle screw may be selected based upon the desired resulting angle 320sought for the resulting placement of the first connecting screw 40.That is, it may be advantageous in certain instances to provide thesecond end 64 of the first connecting screw 40 at a specific location onthe left side 128 on the anterior side 124 of the vertebra 118. Unlessthe first pedicle screw 12 is exactly placed, the resulting location ofthe second end 64 of the first connecting screw 40 may be significantlydifferent than that desired. For this reason, a number of pedicle screwsmay be advantageously provided to the surgeon each having a differentlength and a different engaging portion 22 with respect to the angle ofconnection of the first connecting screw 40 to the engaging portion 22.By having a number of choices available to the surgeon, and based uponthe angle of the bore opening 310, the first pedicle screw 12 may beselected as having an engaging portion 22 that will provide the angle320 that will result in the second end 64 of the first connecting screw40 being positioned at the desired location on the anterior side 124 ofthe vertebra 118.

[0214] Anterior side 124 placement of the first pedicle screw 12 withinthe vertebra 118 provides numerous additional advantages including thedimensions of the first pedicle screw 12 and resulting stability thatmay be achieved from such placement. For example, the first pediclescrew 12, such as that illustrated in FIGS. 4 and 13, may be readilyutilized for these purposes, and may achieve advantageous stabilizationby being placed from the anterior 124 side of the vertebra 118. Forexample, with respect to the first pedicle screw 12 illustrated in FIG.13, it can be seen that the diameter 232 of the reinforced portion 230is slightly smaller than the diameter 246 of the plurality of threads244 according to one aspect.

[0215] Since the reinforced portion 230 will not obtain the threadingengagement, it is necessary for the plurality of threads 244 of thefirst pedicle screw 12 to be slightly larger to achieve a satisfactoryanchoring and threading engagement of the first pedicle screw 12.Otherwise, the reinforced portion 230 might have the affect of smoothingthe opening such that the plurality of threads 244 do not successfullyengage within the vertebra 118.

[0216] Conversely, anterior side 124 placement of the pedicle screwallows for the plurality of threads 238 near the distal end 102 of thefirst pedicle screw 12 to be of a maximum diameter 240 for optimumanchoring and stabilization of the pedicle screw within the vertebra 118and particularly within the pedicle portion 120. At the same time, thediameter 232 of the reinforced portion 230 may be of a maximum diameterfor reinforcement to optimize the connection and engagement of the firstconnecting screw 40 and such structure will not reduce or minimize theengagement of the first pedicle screw 12 with the vertebra 118. Thereason for this is that the plurality of threads 238 will be in front ofthe reinforced portion 230 when anteriorly placed versus behind thereinforced portion 230, as is the case with the plurality of threads 244when the pedicle screw 12 is posteriorly placed. In one aspect, diameter232 of the reinforced portion 230 is similarly sized relative to thediameter 246 of the plurality of threads 244 or any other threadsprovided on the shaft 16. However, numerous configurations of shaft 16sized and thread sizes will readily suggest themselves to one ofordinary skill in the art and are within the spirit and scope of thepresent invention.

[0217] It should be appreciated that a variety of configurations ofpedicle screws have been disclosed and shown herein and any of thevarious configurations may be utilized both for posterior placement ofthe first pedicle screw 12 as well as for anterior placement of thefirst pedicle screw 12. Furthermore, it will be appreciated that anumber of tools, such as the tool 280 illustrated in FIGS. 17 and 18,have been shown and described and may be readily implemented on thefirst pedicle screw 12 for anterior placement.

[0218]FIG. 22 illustrates the first pedicle screw 12 connecting to theguide member 150 for proper alignment of the connecting screw, such asthe first connecting screw 40 to the first pedicle screw 12. In oneaspect, the present invention is directed to the vertebra stabilizationassembly 10 wherein the complete procedure may be accomplished from theanterior side 124 of the vertebra 118. The procedure for such placementmay include drilling a hole utilizing a drill or other device orimplement through the outer surface of the anterior side 124 of thevertebra 118 to penetrate the hard outer bone surface.

[0219] Thereafter utilizing technology typically employed for suchpurposes, such as an image intensifier, x-ray and templates, and/orother stealth technology, a K-wire or other drill or penetratingimplement may be utilized to penetrate in a direction toward theposterior side 122 along a line 326. The K-wire may be obliquely placedthrough the vertebral body into the pedicle 120 on the right side 126. Acannulated drill may be utilized to drill over the K-wire to ream out ahole or opening for placement of the first pedicle screw 12 therein. Thedrill and K-wire may be removed and the first pedicle screw 12 may beanteriorly placed in the drilled opening substantially along the line326 for proper placement of the first pedicle screw 12 in the vertebra118. This aspect, as previously discussed, advantageously provides forselecting, in advance, the proper pedicle screw, such as the firstpedicle screw 12, having the engaging portion 22 to achieve the desiredangle of connection of the connecting screw, such as the firstconnecting screw 40.

[0220] Another advantage of anterior placement of the first pediclescrew 12 is that it provides the opportunity for stabilization from theposterior side 122 when such may be desirable. In this aspect, the firstpedicle screw 12, such as that illustrated and previously disclosedherein in a number of different embodiments, may be utilized byplacement initially from the anterior side 124 such that the distal end102 is anchored substantially in the pedicle 120 portion of the vertebra118. Thereafter, the first pedicle screw 12 may be utilized forconnection of connecting members, such as the connecting member 50, forstandard posterior anchoring and stabilization when such is necessarybecause of a failure to achieve adequate stabilization from the anteriorside 124 as preferably provided herein.

[0221] Under the preferred anterior stabilization and when the firstpedicle screw 12 is placed from the anterior side 124 of the vertebra118, the first pedicle screw 12 is provided with a coupling portion 100near the head 60 of the first pedicle screw 12, substantially as shownin FIG. 22.

[0222] Utilization of the vertebral stabilization assembly 10 accordingto the aspect illustrated in FIG. 22, has the additional advantage ofcompletely eliminating rotation of the patient during the procedure.However, it will be appreciated that there may be certain instances whenit is necessary or useful to rotate the patient for posterior access tothe vertebra 118 and such rotation will not reduce or detract from theadvantages of the vertebral stabilization assembly 10 of the presentinvention in that a significant portion or all of the procedure may beachieved from the anterior side 124 of the vertebra 118. This presents asignificant advantage in that rotation of the patient takes considerabletime and eliminating the necessity for such rotation shortens the timeperiod required for the procedure.

[0223] Once the first pedicle screw 12 has been placed on the anteriorside 124 of the vertebra 118 substantially as shown and discussed abovewith respect to FIG. 22, the guide member 150 may be connected to thefirst pedicle screw 12 at the coupling portion 100 in a manner similarto that previously shown and described with respect to the couplingportion 100 and a guide member 150. Utilization of the guide member 150as well as the connection of the connecting screws, such as the firstand second connecting screws 40 and 42, as well as the bracket 50remains substantially similar to that previously shown and describedherein.

[0224] It should be appreciated that it is within the scope of thepresent invention to anteriorly place the first pedicle screw 12 on theleft anterior side 124, similar to that shown in FIG. 8 except the firstpedicle screw 12 is placed from the anterior instead of posterior of thevertebra 118. In fact, in some instances, anterior placement on the leftside may be advantageous. The reason that this placement may bepreferable is that the angle of the shaft 16 of the first pedicle screw12 is more shallow with respect to the first connecting screw 40. Thisshallower angle will require a smaller guide member 150 and result inthe surgery being performed in a smaller physical area. Since space islimited in the cavity of the patient, this configuration may be usefulin some circumstances. Also, anterior placement of the pedicle screw onthe left side may be utilized as a salvage when the right side becomesfractured or the desired stabilization is not obtained on the right sideof the vertebra 118.

[0225]FIG. 23 illustrates another aspect of the engaging portion 22 ofthe first pedicle screw 12 according to another aspect of the presentinvention. As previously discussed, depending upon the oblique angle ofplacement of the first pedicle screw 12 with respect to the vertebra118, the angle of engagement of the first connecting screw 40 with thefirst pedicle screw 12 may necessarily vary. For this reason, thepresent invention is further directed to an engaging opening 330 whereinthe engaging portion 22 is retained within the shaft 16 of the firstpedicle screw 12.

[0226] In this manner, the engaging portion 22 may be retained in themanner such that the engaging portion 22 may be rotated to receive thefirst connecting screw 40 at various angles 332. Although two angles 332are shown, a variety of angles may be achieved utilizing the presentaspect of the engaging portion 22. The engaging portion 22 may beretained on bearings or other floating structural devices within theengaging opening 330, such that when the first connecting screw 40 iscoupled with the engaging portion 22, the engaging portion 22 becomesfixed with respect to the initial angle 332 of engagement.

[0227] Such variable positioning of the engaging portion 22 can furtherbe obtained by a hinge or a latch connected to the engaging portion 22for hinging or latching rotation at the engaging portion 22 within theengaging opening 330. Also, the engaging portion 22 may be provided on arotational or ratcheted body (not shown) within the engaging opening330. It will be appreciated that a wide variety of structures may beutilized for obtaining and achieving an engaging portion, such as theengaging portion 22 to obtain various angulation, such as the angles 332of connection of the first pedicle screw 12 relative to the firstconnecting screw 40 and are well known to those of ordinary skill in theart and are within the spirit and scope of the present invention and forbrevity will not be further discussed herein.

[0228] The advantage of the engaging portion 22 adapted for angularadjustment is that it eliminates the need for a number of pedicle screwshaving different engaging portions with different angles for connectionto the first connecting screw 40. However, it should be appreciated thatin other aspects the engaging portion 22 is a fixed and rigid structurefor engagement of the first connecting screw 40 and, as such, aplurality of pedicle screws may be necessary each having a differentangle of engagement of the first connecting screw 40 at the engagingportion 22 based upon the angle of placement of the first pedicle screw12 in the vertebra 118.

[0229] Furthermore, according to other aspects of the present invention,it is anticipated that a variety of pedicle screws, such as the firstpedicle screw 12, having significantly different lengths will beutilized for various adaptations and placements. Also, a variety ofpedicle screws, such as the first pedicle screw 12, where the fixedengaging portions 22 is available in variety of angles of connection ofthe connecting screw relative to the shaft 16 of the first pedicle screw12.

[0230]FIG. 24 illustrates another aspect of the present invention of thefirst pedicle screw 12, wherein only a portion of the shaft 16 of thefirst pedicle screw 12 is illustrated. In this aspect the shaft 16 isprovided with at least one non-continuous thread 336 extendingcircumferentially about the shaft 16 of the first pedicle screw 12. Inthis manner, a first portion 338 of the non-continuous threads 336extend circumferentially about a portion of the shaft 16 while a secondportion of the non-continuous threads 336 extend about a second portionof the shaft 16.

[0231] A gap 342 is disposed between the first portion 338 and thesecond portion 340 of the non-continuous threads 336. The gap is aportion of the shaft 16 that is not provided with threads and may be ofvarious circumferential dimensions and be suitable for these purposes.It will be appreciated that frequently the first pedicle screw 12 andparticularly the threads on the shaft 16 may cause aggravation andirritation to nerves adjacent the vertebra 18. Once it has beendetermined that a nerve is aggravated by the placement of the firstpedicle screw 12, adjustment or replacement of the first pedicle screw12 is necessitated. Frequently, this requires completely removing andrelocating the first pedicle screw 12 according to another oblique anglein the vertebra 118. By providing the first pedicle screw 12 having oneor more of the non-continuous threads 336, according to the presentaspect, aggravation of the nerve may be potentially alleviated by only aminor rotation of the first pedicle screw 12 since it is likely that thethread on the shaft 16 may be causing the irritation or aggravation ofthe nerve. Thus, upon a minor or slight rotation of the first pediclescrew 12 the gap 342 will replace, for example, the non-continuousthreads 336 and alleviate the aggravation of the nerve and, thus,eliminate the necessity for completely removing and repositioning thefirst pedicle screw 12. It will be appreciated that the position anddistribution of the non-continuous threads 336 with respect to theirsymmetrical placement may be altered or modified and are within thespirit and scope of the present invention as described and disclosedherein and will readily suggest themselves to one of ordinary skill inthe art.

[0232]FIG. 25 illustrates another aspect of the vertebral stabilizationassembly 10 having dual pedicle screws 400 a and 400 b for placement inthe vertebra 118 to provide additional stability. The pedicle screws 400a and 400 b are substantially similar to the first and second pediclescrews 12 and 14 in many aspects. The dual pedicle screws 400 a and 400b, however, are provided with engaging portions 402 a and 402 b relativeto one another such that a connecting screw 404, substantially similarto the first connecting screw 40, may be connected to both the dualpedicle screws 400 a and 400 b. The connecting screw 404 may be providedwith a first end 406 adapted to be received by the engaging portion 402a of the pedicle screw 400 a. The connecting screw 404 is furtherprovided with a shaft 408, at least a portion of which is operative toconnect to the engaging portion 402 b of the pedicle screw 400 b. Thedual pedicle screws 400 a and 400 b must be constructed and configuredsuch that upon placement in the vertebra 118 pedicle screws 400 a and400 b provide for such connection by the connecting screw 404.

[0233] In some aspects the engaging portion 402 b of the pedicle screw400 b may be an opening sufficient to receive the connecting screw 404through the opening, as well as for engaging the shaft of 408 of theconnecting screw 404. It is readily apparent that this configuration ofthe dual pedicle screws 400 a and 400 b provides significant vertebralsupport and stability. Furthermore, although only the vertebra 118 isshown it should be understood that the present configuration, includingthe dual pedicle screws 400 a and 400 b and a connecting screw 404, maybe utilized for placement in a plurality of vertebra to provideincreased stabilization for a plurality of vertebra for the purposespreviously discussed and disclosed herein.

[0234] In another aspect, the present invention provides a fixation tool430 for properly aligning the dual pedicle screws 400 a and 400 b forplacement in the vertebra 118. Accurate alignment and placement of thedual pedicle screws 400 a and 400 b, according to one aspect, may beadvantageously provided by utilizing the fixation tool 430. The fixationtool 430 is provided with alignment members 432 a and 432 b to achievethe proper alignment of the dual pedicle screws 400 a and 400 b in thevertebra 118. The alignment members 432 a and 432 b may be similar tothe alignment member 156 of the guide member 150 previously disclosedand described above.

[0235] It may be advantageous, according to other aspects, to provideindicia on the dual pedicle screws 400 a and 400 b to provide for theproper alignment of the pedicle screws 400 a and 400 b. In other aspectsthe fixation tool 430 may be unnecessary when employing x-ray, stealth,or other imaging technologies to ensure the accurate alignment andplacement of the dual pedicle screws 400 a and 400 b. In other aspects,however, the fixation tool 430 may be used such that the dual pediclescrews 400 a and 400 b may be simultaneously placed to ensure theengaging portions 402 a and 402 b of the dual pedicle screws 400 a and400 b, respectively, are in proper alignment for connection by theconnecting screw 404.

[0236] The pedicle screws 400 a and 400 b may also utilize guiding andlocating techniques, previously discussed above, such that the pediclescrews 400 a and 400 b may be placed posteriorly, percutaneously orotherwise, and the connecting screw 404 may be placed anteriorly. Oncethe pedicle screws 400 a and 400 b have been inserted, the patient maythen be rotated. A guide member, such as the guide member 150 may beutilized for connection and alignment of the connecting screw 404, aspreviously discussed above.

[0237] Thus, the guide member 150 is coupled, for example, to thepedicle screw 400 a such that the alignment member 156 is operable toproperly align the connecting screw 404 for coupling to the dual pediclescrews 400 a and 400 b. This may include, as previously discussed,drilling a tap hole or other guiding hole for accurate placement andalignment of the connecting screw 404. In any event, the connectingscrew 404 may then be connected to the dual pedicle screws 400 a and 400b in a configuration substantially as illustrated in the present aspect.

[0238]FIG. 26 illustrates another aspect of the present inventionutilizing dual pedicle screws 400 a and 400 b for anterior placement. Itwill be appreciated, as previously discussed, that one advantage of thepresent invention is placement of the pedicle screws from the anteriorside 124 of the vertebra 118. The current aspect illustrates anotherembodiment of the fixation tool 430 having alignment members 432 a and432 b for alignment of the dual pedicle screws 400 a and 400 b,respectively, from the anterior side 124 of the vertebra 118. Thefixation tool 430 may also combine the alignment features of the guidemember 150 (See FIG. 25) to achieve the proper alignment of theconnecting screw 404 as well.

[0239] In one aspect, the fixation tool 430 may be implemented bydetermining the point 440 on the vertebra 118 to desirably place theconnecting screw 404. A pin, tack or other means may be employed toposition and orient the alignment portion 442 which will provide theproper alignment for the connecting screw 404. Once the desiredplacement for the connecting screw 404 has been located, the dualpedicle screws 400 a and 400 b may then be aligned and placed in thevertebra 118 utilizing the alignment members 432 a and 432 b of thealignment tool 430. In some aspects the alignment members 432 a and 432b may be provided with an inner and an outer barrel (not shown) whereinthe inner barrel may be utilized to drill a guide hole in the vertebra118 and the outer barrel may then be used to guide the pedicle screws400 a and 400 b into place.

[0240]FIG. 27 illustrates another aspect of the present inventionwherein the connecting screw 404 may be placed across the body of thevertebra 118. In many instances it may be advantageous to position theconnecting screw 404 in such a manner for coupling of the connectingscrew 404 to adjacent vertebra similarly stabilized. It is within thespirit and scope of the present invention that such placement of theconnecting screw 404 may still utilize the additional stability providedby one or more pedicle screws 400 a and 400 b. The pedicle screw 400 bis illustrated in phantom to denote that such placement of theconnecting screw 404 may not necessitate placement of dual pediclescrews 400 a and 400 b and only one pedicle screw 400 a may besufficient to provide the desired stability in these instances.

[0241] Thus, it is apparent that there has been provided, in accordancewith the present invention, a vertebral stabilization assembly andmethod that satisfies one or more of the advantages set forth above.Although the preferred embodiment has been described in detail, itshould be understood that various changes, substitutions, andalterations can be made herein without departing from the scope of thepresent invention, even if all of the advantages identified above arenot present. For example, the various embodiments shown in the drawingsherein illustrate that the present invention may be implemented andembodied in a variety of different ways that still fall within the scopeof the present invention.

[0242] Also, the techniques, designs, elements, and methods describedand illustrated in the preferred embodiment as discrete or separate maybe combined or integrated with other techniques, designs, elements, ormethods without departing from the scope of the present invention. Otherexamples of changes, substitutions, and alterations are readilyascertainable by one skilled in the art and could be made withoutdeparting from the spirit and scope of the present invention.

What is claimed is:
 1. A guide member for placement of a connectingscrew of a vertebral stabilization assembly, the guide membercomprising: a coupling portion operable to couple with a couplingportion of a pedicle screw of the vertebral stabilization assembly; anoffset member connected to the coupling portion of the guide member; andan alignment member connected to the offset member, the alignment memberoperable for alignment of the connecting screw of the vertebralstabilization assembly with a portion of the pedicle screw of thevertebral stabilization assembly.
 2. The guide member of claim 1,wherein the coupling portion of the guide member is operable to couplewith the coupling portion of the pedicle screw such that the offsetmember extends in a direction relative to the coupling of the couplingportion of the guide member to the coupling portion of the pediclescrew.
 3. The guide member of claim 1, wherein the offset member isfurther provided with a first end and a second end, and wherein thefirst end of the offset member is connected to the coupling portion andwherein the second end of the offset member is coupled to the alignmentmember.
 4. The guide member of claim 3, wherein the offset member ispositionable relative to the coupling of the coupling portion with anend portion of the pedicle screw.
 5. The guide member of claim 3,wherein the offset member arcuately extends from the coupling portion ofthe guide member.
 6. The guide member of claim 1, wherein the couplingportion of the guide member couples to the coupling portion of thepedicle screw such that the offset member positions the alignment membersubstantially aligned adjacent the coupling portion of the pediclescrew.
 7. The guide member of claim 6, wherein the alignment membersubstantially aligns adjacent an engaging portion of a shaft of thepedicle screw.
 8. The guide member of claim 6, wherein the alignmentmember substantially aligns adjacent an opening on a shaft of thepedicle screw.
 9. The guide member of claim 8, wherein the alignmentmember provides alignment for threading the connecting screw in thevertebra adjacent the opening in the pedicle screw.
 10. The guide memberof claim 8, wherein the alignment member provides alignment forattachment of the connecting screw of the vertebral stabilizationassembly to the pedicle screw.
 11. The guide member of claim 1, whereinthe alignment member is further defined as tubular member having a firstend, a second end and a opening extending through the tubular memberfrom the first end to the second end.
 12. The guide member of claim 11,wherein the opening extending through the tubular member is providedwith a diameter sufficient to receive the connecting screw of thevertebral stabilization assembly through the opening in the tubularmember for alignment with an engaging portion of a shaft of the pediclescrew of the vertebral stabilization assembly.
 13. The guide member ofclaim 1, wherein the coupling portion is provided with a threaded memberadjacent an end of the coupling portion, the threaded member operable tothreadingly engage the coupling portion of the pedicle screw.
 14. Theguide member of claim 1, wherein the coupling portion is further definedas having an angularly configured opening to matingly receive anangularly configured end of the pedicle screw for attachment of theguide member to the pedicle screw.
 15. The guide member of claim 1,wherein the coupling portion is further defined as having an angularlyconfigured end to be matingly received by an angularly configuredopening of the pedicle screw to attach the guide member to the pediclescrew.
 16. The guide member of claim 1 further including a secondcoupling portion connected to the offset member, the second couplingportion operable to couple with a coupling portion of a second pediclescrew for positioning of the pedicle screw and the second pedicle screwin the vertebra for alignment of the pedicle screw and the secondpedicle screw operably with the connecting screw such that theconnecting screw connects with the pedicle screw and the second pediclescrew.
 17. A vertebral stabilization assembly for stabilizing vertebraecomprising: a first pedicle screw having a shaft provided with athreaded portion operable for threading engagement of the first pediclescrew with a first vertebra, the shaft having an engaging portion; afirst connecting screw having a first end adapted to be received by theengaging portion of the first pedicle screw; a second pedicle screwhaving a shaft provided with a threaded portion operable for threadingengagement of the pedicle screw with a second vertebra, the shaft havingan engaging portion; a second connecting screw having a first endadapted to be received by the engaging portion of the second pediclescrew; and a connecting member having a first end and a second end, thefirst end of the connecting member connected to the first connectingscrew positionable in the first vertebra, the second end of theconnecting member connected to the second connecting screw positionablein the second vertebra for stabilization of the first vertebra and thesecond vertebra.
 18. The vertebral stabilization assembly of claim 17,wherein the connecting member is defined as a rod.
 19. The vertebralstabilization assembly of claim 18, wherein the first and secondconnecting screws are each provided with an opening in a second endthereof and wherein the first end of the rod is positionable in theopening in the second end of the first connecting screw and wherein thesecond end of the rod is positionable in the opening in the second endof second connecting screw.
 20. The vertebral stabilization assembly ofclaim 19, further comprising a first and second tensioning mechanism,the first tensioning mechanism tensioningly engaging the first end ofthe rod in the opening in the second end of the first connecting screwand the second tensioning mechanism tensioningly engaging the second endof the rod in the opening in the second end of the second connectingscrew.
 21. The vertebral stabilization assembly of claim 17, wherein thefirst and second connecting screws are provided with coupling portionsoperable to couple the first and second connecting screws with theconnecting member.
 22. The vertebral stabilization assembly of claim 21,wherein the coupling portions of the first and second connecting screwsare further defined as a threaded end of the first and second connectingscrews.
 23. The vertebral stabilization assembly of claim 22, whereinthe threaded end of the first and second connecting screws areconnectable to the connecting member by bolts.
 24. The vertebralstabilization assembly of claim 17, wherein the connecting memberconnected to the first and second connecting screw is sized to retainthe first vertebra disposed a distance from the second vertebra.
 25. Thevertebral stabilization assembly of claim 17, wherein the connectingmember is sized to retain the first vertebra disposed so as to preventcontact with the second vertebra.
 26. The vertebral stabilizationassembly of claim 17, wherein the connecting member is defined as abracket.
 27. The vertebral stabilization assembly of claim 17, whereinthe connecting member is defined as a plate.
 28. The vertebralstabilization assembly of claim 17, wherein the first and second pediclescrews are operable to engage a first and second lumbar vertebra,respectively.
 29. The vertebral stabilization assembly of claim 17,further including a bore screw having a shaft and a threaded portion,the bore screw operable to bore an opening in the vertebra for placementof the first and second pedicle screws.
 30. The vertebral stabilizationassembly of claim 29, wherein the bore screw is further provided with anengaging portion on a distal end of the shaft of the bore screw, theengaging portion operably coupleable to a tool for removing the borescrew from an anterior side of the vertebra when the bore screw isinitially placed from a posterior side of the vertebra.
 31. Thevertebral stabilization assembly of claim 29, further including anindicator light extendable through the bore opening, the indicator lightvisible from an anterior side of the vertebra when the indicator lightis extended through the bore opening from a posterior side of thevertebra.
 32. The vertebral stabilization assembly of claim 17, furtherincluding a tool operable to engage at least the first connecting screwfor connection of at least the first connecting screw to the firstpedicle screw.
 33. The vertebral stabilization assembly of claim 17,further including a tool operable to engage at least the firstconnecting screw for removal of at least the first connecting screw fromthe first pedicle screw.
 34. The vertebral stabilization assembly ofclaim 17, further including a tool operable to engage at least the firstpedicle screw for threading engagement of at least the first pediclescrew in the first vertebra.
 35. The vertebral stabilization assembly ofclaim 17, further including a tool operable to engage at least the firstpedicle screw for stabilization of at least the first pedicle screwwhile removing the connecting screw.
 36. A vertebral stabilizationassembly having dual pedicle screws for placement in a vertebra,comprising: a first pedicle screw having a shaft provided with athreaded portion operable for threading engagement of the first pediclescrew with a first vertebra, the shaft having an engaging portion; asecond pedicle screw having a shaft provided with a threaded portionoperable for threading engagement of the first pedicle screw with afirst vertebra, the shaft having an engaging portion; and a connectingscrew provided with a first end and a shaft, the first end of theconnecting screw adapted to be received by the engaging portion of thefirst pedicle screw, the shaft of the connecting screw adapted forconnection to the engaging portion of the second pedicle screw.
 37. Apedicle screw for securing a connecting screw of a vertebralstabilization assembly, the pedicle screw comprising: a shaft having athreaded portion operable for threading engagement of the pedicle screwwith a vertebra; a engaging portion provided on the shaft, the engagingportion operable to receive a connecting screw of the vertebralstabilization assembly; and a coupling portion provided on the shaft,the coupling portion adapted to connect a guide member of the vertebralstabilization assembly.
 38. The pedicle screw of claim 37, wherein theshaft is further defined as having a first end and a second end suchthat the threaded portion is adjacent at least the first end and thesecond end is operable to receive rotational engagement for rotating thepedicle screw for placement in the vertebra.
 39. The pedicle screw ofclaim 37, wherein the engaging portion is further defined as an openingon the shaft operable to receive the connecting screw of the vertebralstabilization assembly.
 40. The pedicle screw of claim 39, wherein theopening is further defined as extending through the shaft from a shaftfirst side to a shaft second side.
 41. The pedicle screw of claim 39,wherein the opening is coupleable with the connecting screw to providestabilizing engagement of the connecting screw.
 42. The pedicle screw ofclaim 39, wherein the opening is coupleable with the connecting screw toprovide rigid engagement with the connecting screw.
 43. The pediclescrew of claim 39, wherein the opening is coupleable with the connectingscrew to provide locking engagement with the connecting screw.
 44. Thepedicle screw of claim 39, wherein the opening is coupleable with theconnecting screw to provide threaded engagement with the connectingscrew.
 45. The pedicle screw of claim 37, wherein the coupling portionof the pedicle screw is associated with the engaging portion such thatwhen the guide member is coupled to the coupling portion an alignmentmember of the guide member is aligned with the engaging portion of thepedicle screw.
 46. The pedicle screw of claim 37, wherein the couplingportion is further defined as an opening operable for threadingengagement.
 47. The pedicle screw of claim 37, wherein the shaft isfurther defined as a substantially rigid shaft constructed from amaterial selected from the group consisting of steel, aluminum, metallicmaterials and polymeric materials.
 48. The pedicle screw of claim 37,wherein the shaft includes a cannulated passageway through the shaftfrom a first end of the shaft to a second end of the shaft.
 49. Thepedicle screw of claim 37, wherein the pedicle screw is operable toengage at least a portion of a pedicle of a lumbar vertebra.
 50. Thepedicle screw of claim 37, wherein the pedicle screw is operable toengage at least a portion of a pedicle of a thoracic vertebra.
 51. Thepedicle screw of claim 37, wherein the shaft of the pedicle screw isprovided with a first threaded portion and a reinforced portion.
 52. Thepedicle screw of claim 51, wherein the reinforced portion of the shaftof the pedicle screw is further defined as having a diameter that isgreater than a diameter of the first threaded portion of the shaft. 53.The pedicle screw of claim 51, wherein the reinforced portion of theshaft of the pedicle screw is further defined as having a diameter thatis greater than the diameter of the shaft adjacent the first threadedportion and about equal to a diameter measured from an outermost edge ofa plurality of threads provided on the first threaded portion of theshaft.
 54. The pedicle screw of claim 51, further includes a secondthreaded portion on the shaft and wherein the reinforced portion of theshaft of the pedicle screw is further defined as having a diameter thatis less than a diameter measured from an outermost edge of a pluralityof threads provided on the second threaded portion of the shaft.
 55. Thepedicle screw of claim 51, wherein the reinforced portion of the shaftof the pedicle screw is substantially adjacent the engaging portion ofthe shaft to reinforce the connection of the connecting screw to thepedicle screw at the engaging portion.
 56. The pedicle screw of claim51, wherein the pedicle screw further includes a second threadedportion, such that the reinforced portion is adjacent the first andsecond threaded portions.
 57. The pedicle screw of claim 37, wherein theshaft is further defined as provided with at least a first grooveextending longitudinally a distance along the length of the shaft, theat least first groove operably received by a tool for engagement of thetool with a first end of the pedicle screw.
 58. The pedicle screw ofclaim 57 wherein the tool is further defined as having a handle operableto be grasped by a hand of an individual, the tool including an engagingportion to engage the grooved first end of the pedicle screw.
 59. Thepedicle screw of claim 37, wherein the pedicle screw is further definedas having an angular end operably received by a tool provided with anangular opening to rotate the pedicle screw relative to the desiredplacement of the connecting screw.
 60. The pedicle screw of claim 59wherein the tool is further defined as the guide member and wherein acoupling portion of the guide member is provided with rectangularopening to receive the first angular end of the pedicle screw to rotatethe pedicle screw relative to the desired placement of the connectingscrew.
 61. The pedicle screw of claim 57, wherein the engaging portionincludes a rotational member operable to adjust an angle of connectionof the connecting screw relative to the shaft of the pedicle screw. 62.The pedicle screw of claim 61, wherein the rotational member is furtherdefined as a ratcheting member.
 63. The pedicle screw of claim 37,wherein the shaft is further provided with a cannulated portion definingan opening extending through the shaft from a first end of the shaft tothe second end of the shaft.
 64. The pedicle screw of claim 63, whereinthe cannulated portion is operable to receive a drill through theopening in the shaft for drilling through a portion of the vertebra. 65.The pedicle screw of claim 63, wherein the cannulated portion isoperable to receive a wire through the opening in the shaft forbreaching an opening through a portion of the vertebra.
 66. The pediclescrew of claim 37, wherein the pedicle screw is further defined asoperable for placement from an anterior side of the vertebra such that aportion of the threaded portion of the shaft anchors in a pedicleportion of the vertebra.
 67. A pedicle screw for anchoring in avertebra, the pedicle screw comprising: a shaft provided with at least afirst and a second non-continuous threaded portions extendingcircumferentially about a portion of the shaft such that at least afirst gap is disposed between the first and second non-continuousthreaded portions, the at least first gap defining a portion of theshaft between the first non-continuous threaded portions and the secondnon-continuous threaded portions; and a head adjacent one end of theshaft provided with an engaging portion operable to receive engagingrotation by a tool for placement of the pedicle screw such that at leasta portion of the pedicle screw anchors in a pedicle portion of thevertebra.
 68. A method for stabilizing a lower vertebra and an uppervertebra from an anterior side of the vertebrae using a vertebralstabilization assembly, the method comprising: inserting a first pediclescrew, which includes a shaft provided with a threaded portion operableto threadingly engage the lower vertebra, into the lower vertebrathrough a pedicle and a vertebral body of the lower vertebra from aposterior side of the lower vertebra, the shaft of the first pediclescrew having an engaging portion operable to receive a first connectingscrew, and the shaft of the first pedicle screw having a couplingportion operable to couple with a guide member; inserting a secondpedicle screw, which includes a shaft provided with a threaded portionoperable to threadingly engage the upper vertebra, into the uppervertebra through a pedicle and a vertebral body of the upper vertebrafrom a posterior side of the upper vertebra, the shaft of the secondpedicle screw having an engaging portion operable to receive a secondconnecting screw, and the shaft of the second pedicle screw having acoupling portion operable to couple with the guide member; locating thecoupling portion of the shaft of the first pedicle screw from ananterior side of the lower vertebra; coupling the guide member to thecoupling portion of the shaft of the first pedicle screw from theanterior side of the lower vertebra; inserting a lower connecting screwincluding a first end adapted to be received by the engaging portion ofthe first pedicle screw and a second end adapted to reside outside thelower vertebra on the anterior side of the lower vertebra, the lowerconnecting screw inserted through the anterior side of the lowervertebra using the guide member; locating the coupling portion of theshaft of the second pedicle screw from an anterior side of the uppervertebra; coupling the guide member to the coupling portion of the shaftof the second pedicle screw from the anterior side of the uppervertebra; inserting an upper connecting screw including a first endadapted to be received by the engaging portion of the second pediclescrew and a second end adapted to reside outside the upper vertebra onthe anterior side of the upper vertebra, the upper connecting screwinserted through the anterior side of the upper vertebra using the guidemember; and connecting the second end of the lower connecting screw ofthe lower vertebra to the second end of the upper connecting screw ofthe upper vertebra with a connecting member.
 69. The method of claim 68,wherein the first and second pedicle screws are posteriorly placed onthe right side of the lower and upper vertebra, respectively, andwherein the lower and upper vertebra are further defined as a lower andupper lumbar vertebra.
 70. The method of claim 68, wherein the first andsecond pedicle screws are posteriorly placed on the right side of thelower and upper vertebra, respectively, and wherein the lower and uppervertebra are further defined as a lower and upper thoracic vertebra. 71.The method of claim 68, wherein the first pedicle screw is furtherprovided with a cannulated shaft having a passageway extending from afirst end to a second end of the first pedicle screw and whereinlocating the coupling portion of the shaft of the first pedicle screwfrom the anterior side of the lower vertebra further includes: extendinga tool operable to drill through a portion of the lower vertebra throughthe passageway of the shaft of the first pedicle screw; and drilling theportion of the lower vertebra such that the tool extends at leastpartially through the anterior side of the lower vertebra.
 72. Themethod of claim 71, wherein the second pedicle screw is further providedwith a cannulated shaft having a passageway extending from a first endto a second end of the second pedicle screw and wherein locating thecoupling portion of the shaft of the second pedicle screw from theanterior side of the upper vertebra further includes: extending the tooloperable to drill through a portion of the upper vertebra through thepassageway of the shaft of the second pedicle screw; and drilling theportion of the upper vertebra such that the tool extends at leastpartially through the anterior side of the upper vertebra.
 73. Themethod of claim 68, wherein coupling the guide member to the first andsecond pedicle screws further includes threadingly coupling the guidemember to the coupling portion of the shaft of the first and secondpedicle screws.
 74. The method of claim 68, wherein coupling the guidemember to the first and second pedicle screws further includes matinglycoupling the guide member to the coupling portion of the shaft of thefirst and second pedicle screws.
 75. The method of claim 68, whereininserting the lower connecting screw further includes: positioning thelower connecting screw in alignment with the engaging portion of thefirst pedicle screw utilizing an alignment member of the guide member;and threading the lower connecting screw through the anterior side ofthe lower vertebra.
 76. The method of claim 75, wherein positioning thelower connecting screw in alignment with the engaging portion of thefirst pedicle screw further includes receiving the lower connectingscrew by the alignment member of the guide member, the guide memberadapted to position the alignment member connected to the guide membersubstantially aligned adjacent the engaging portion of the first pediclescrew when the guide member is coupled to the coupling portion of thefirst pedicle screw.
 77. The method of claim 75, wherein inserting theupper connecting screw further includes: positioning the upperconnecting screw in alignment with the engaging portion of the secondpedicle screw utilizing the alignment member of the guide member; andthreading the upper connecting screw through the anterior side of theupper vertebra.
 78. The method of claim 75, wherein positioning theupper connecting screw in alignment with the engaging portion of thesecond pedicle screw further includes receiving the upper connectingscrew by the alignment member of the guide member, the guide memberadapted to position the alignment member connected to the guide membersubstantially aligned adjacent the engaging portion of the secondpedicle screw when the guide member is coupled to the coupling portionof the second pedicle screw.
 79. The method of claim 68, whereinconnecting the upper connecting screw to the lower connecting screwfurther comprises: providing the connecting member having a first endand a second end; connecting the second end of the lower connectingscrew to the first end of the connecting member; and connecting thesecond end of the upper connecting screw to the second end of theconnecting member.
 80. The method of claim 79, wherein the connectingmember is a plate and wherein the second end of the lower connectingscrew receives the first end of the plate and wherein the second end ofthe upper connecting screw receives the second end of the plate.
 81. Themethod of claim 79, wherein the connecting member is a bracket andwherein the second end of the lower connecting screw receives the firstend of the bracket and wherein the second end of the upper connectingscrew receives the second end of the bracket.
 82. The method of claim79, wherein the connecting member is a rod and wherein the second end ofthe lower connecting screw connects to the first end of the rod andwherein the second end of the upper connecting screw connects to thesecond end of the rod.
 83. A method for stabilizing a lower vertebra andan upper vertebra from an anterior side of the vertebrae using avertebral stabilization assembly, the method comprising: inserting afirst pedicle screw, which includes a shaft provided with a threadedportion operable to threadingly engage the lower vertebra, into thelower vertebra from an anterior side of the lower vertebra such that aportion of the threaded portion of the shaft engages a pedicle portionof the lower vertebra, the shaft of the first pedicle screw having anengaging portion operable to receive a first connecting screw, and theshaft of the first pedicle screw having a coupling portion operable tocouple with a guide member; inserting a second pedicle screw, whichincludes a shaft provided with a threaded portion operable tothreadingly engage the upper vertebra, into the upper vertebra from ananterior side of the upper vertebra such that a portion of the threadedportion of the shaft engages a pedicle portion of the upper vertebra,the shaft of the second pedicle screw having an engaging portionoperable to receive a second connecting screw, and the shaft of thesecond pedicle screw having a coupling portion operable to couple withthe guide member; locating the coupling portion of the shaft of thefirst pedicle screw from an anterior side of the lower vertebra;coupling the guide member to the coupling portion of the shaft of thefirst pedicle screw from the anterior side of the lower vertebra;inserting a lower connecting screw, which includes a first end adaptedto be received by the engaging portion of the first pedicle screw and asecond end adapted to reside outside the lower vertebra on the anteriorside of the lower vertebra, the lower connecting screw inserted throughthe anterior side of the lower vertebra using the guide member; locatingthe coupling portion of the shaft of the second pedicle screw from ananterior side of the upper vertebra; coupling the guide member to thecoupling portion of the shaft of the second pedicle screw from theanterior side of the upper vertebra; inserting an upper connectingscrew, which includes a first end adapted to be received by the engagingportion of the second pedicle screw and a second end adapted to resideoutside the upper vertebra on the anterior side of the upper vertebra,the upper connecting screw inserted through the anterior side of theupper vertebra using the guide member; and connecting the second end ofthe lower connecting screw of the lower vertebra to the second end ofthe upper connecting screw of the upper vertebra with a connectingmember.